Controlled sympathectomy and micro-ablation systems and methods

ABSTRACT

A catheter system for controlled sympathectomy procedures is disclosed. A catheter system for controlled micro ablation procedures is disclosed. Methods for performing a controlled surgical procedure are disclosed. A system for performing controlled surgical procedures in a minimally invasive manner is disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. ProvisionalApplication No. 61/948,963, filed Mar. 6, 2014, entitled “ControlledSympathectomy and Micro-Ablation Systems and Methods”, and is acontinuation-in-part application claiming the benefit of U.S. patentapplication Ser. No. 14/374,446, filed on Jul. 24, 2014, a nationalstage application of International Application No. PCT/US2013/023157,which claims benefit of and priority to U.S. Provisional ApplicationSer. No. 61/590,812 filed on Jan. 26, 2012, and U.S. ProvisionalApplication Ser. No. 61/613,097 filed on Mar. 20, 2012, entitled“Controlled Sympathectomy and Micro-Ablation Systems and Methods”, theentire contents of which are each incorporated by reference herein.

TECHNICAL FIELD

The present disclosure relates to the field of minimally invasivesympathectomy. The disclosure relates to methods for locating,monitoring, and/or mapping nerve distributions before, during, and/orfollowing an ablation process facilitated by way of catheterizationprocedures. The disclosure relates to systems and methods for monitoringthe extent of an ablation process as it pertains to a surgical goal,such as denervation. The disclosure also relates to catheter systemsspecifically designed for use in vascular nerve monitoring and ablation.

BACKGROUND

Congestive heart failure, hypertension, diabetes, and chronic renalfailure have many different initial causes; however, all may includesome form of renal sympathetic nerve hyperactivity. Renal sympatheticnerves communicate signals with sympathetic centers located in thespinal cord and brain via afferent renal nerve activity, increasingsystemic sympathetic tone; meanwhile, through efferent activity, renalnerves and arteries participate in sympathetic hyperactivity in responseto signals from the brain, further increasing systemic sympathetic tone.

Sympathetic activation can initially be beneficial but eventuallybecomes maladaptive. In a state of sympathetic hyperactivity, a numberof pathological events take place: abnormalities of hormonal secretionsuch as increased catecholamine, renin and angiotensin II levels,increased blood pressure due to peripheral vascular constriction and/orwater and sodium retention, renal failure due to impaired glomerularfiltration and nephron loss, cardiac dysfunction and heart failure dueto left ventricular hypertrophy and myocyte loss, stroke, and evendiabetes. Therefore, modulation (reduction/removal) of this increasedsympathetic activity can slow or prevent the progression of thesediseases.

Although ablation of such nerves can have positive effects on drugresistant hypertension and glucose metabolism abnormality currentmethodologies for denervation (e.g. ablation) are conducted withoutadequate feedback (with respect to the site of a denervation event, theextent of denervation, the effect of denervation on local physiology,etc.).

SUMMARY

Embodiments of the invention provide a tool for monitoring, evaluating,mapping, and/or modulating electrophysiological activity in the vicinityof a lumen within a body. Furthermore, embodiments of the inventionprovide a system and method for evaluating the sympathetic tone of asubject. Still further, embodiments of the invention provide a systemfor neuromodulating an anatomical site in the vicinity of a lumen withina body.

The above embodiments are wholly or partially met by devices, systems,and methods according to the appended claims in accordance with thepresent disclosure. Features and aspects are set forth in the appendedclaims, in the following description, and in the annexed drawings inaccordance with the present disclosure.

According to a first aspect there is provided, a tool for monitoringelectrophysiological activity within the vicinity of a lumen, the toolincluding a microfinger in accordance with the present disclosure havinga substantially elongate structure configured so as to bias a regionthereof against a wall of the lumen upon deployment within the lumen,and a sensing tip in accordance with the present disclosure electricallyand mechanically coupled to the microfinger in the vicinity of theregion, configured to interface with the wall of the lumen, the sensingtip configured to convey one or more electrophysiological signalsassociated with the activity.

In aspects, the tool may be a microsurgical tool in accordance with thepresent disclosure.

In aspects, one or more of the electrophysiological signals may berelated to one or more of water concentration, tone, evoked potential,electrolyte or solute concentration, remote stimulation of nervousactivity, an electromyographic signal [EMG], a mechanomyographic signal[MMG], a local field potential, an electroacoustic event, vasodilation,vessel wall stiffness, muscle sympathetic nerve activity (MSNA), centralsympathetic drive (e.g. bursts per minute, bursts per heartbeat, etc.),tissue tone, nerve traffic (e.g. post ganglionic nerve traffic in theperoneal nerve, celiac ganglion, superior mesenteric ganglion,aorticorenal ganglion, renal ganglion, and/or related nervous systemstructures), combinations thereof, or the like.

In aspects, one or more of the sensing tips may include one or moreelectrodes, a needle electrode, a force sensor, mechanomyographic (MMG)sensing element, a strain sensor, a compliance sensor, a temperaturesensor, combinations thereof, or the like each in accordance with thepresent disclosure. In aspects, one or more sensing tips may beelectrically coupled with a microcircuit, the microcircuit configured tocondition the signal.

In aspects, one or more of the microfingers may be configured so as tosubstantially embed the sensing tip into the wall of the lumen, tosubstantially maintain contact with the wall of the lumen while it isswept longitudinally down the lumen and/or circumferentially around thelumen, to substantially maintain a constant force against the wall ofthe lumen during relative movement there between, to substantiallyelectrically isolate the sensing tip from a cavity of the lumen, toplunge the electrode (particularly a needle electrode) into the wall ofthe lumen upon deployment, combinations thereof, and the like.

In aspects, the microfinger may include an active material element inaccordance with the present disclosure, configured to alter the contactforce between the region or the sensing tip, and the wall upon receiptof a control signal.

In aspects, the microfinger may be configured so as to be deployed froma delivery catheter. In aspects, the delivery catheter may have adiameter less than 3 mm, less than 2 mm, less than 1 mm. In aspects, atleast a portion of the delivery catheter may have a diameter of lessthan 0.75 mm, less than 0.5 mm, less than 0.25 mm so as to access aminiature lumen within a body.

In aspects, the microfinger may have a characteristic width of less than150 um, less than 100 um, less than 75 um, less than 50 um, less than 25um, less than 10 um, less than 5 um.

In aspects, a plurality of microfingers may be configured to form acage, a mesh, or a stent-like structure, to independently maintaincontact with the wall during relative movement there between,combinations thereof, or the like.

According to aspects there is provided use of a microsurgical tool inaccordance with the present disclosure to monitor electrophysiologicalactivity in the vicinity of a vessel, an artery, a vein, a renal artery,similar structures, or the like.

According to aspects there is provided use of a microsurgical tool inaccordance with the present disclosure to perform a surgical procedure.

According to aspects there is provided, a system for neuromodulating ananatomical site in the vicinity of a lumen, including a subsystemconfigured to perform a surgical or interventional procedure on theanatomical site, a microsurgical tool in accordance with the presentdisclosure, configured to monitor electrophysiological activity in thevicinity of the site; and a control unit configured to accept signalsfrom the microsurgical tool, and to adjust the surgical proceduredependent upon the signals, to display the signals, to evaluate thesurgical procedure dependent upon the signals, to plan a surgical pathdependent upon the signal, to determine the extent of the proceduredependent upon the signals, combinations thereof, or the like.

In aspects, the surgical or interventional procedure may include anablation, an excision, a cut, a burn, a radio frequency ablation,radiosurgery, an ultrasonic ablation, freezing, ionizing radiation, anabrasion, a biopsy, delivery of a substance, delivery of a toxic ormodulating substance, combinations thereof, or the like.

In aspects, the system may include a stimulation and/or ablationelectrode configured so as to convey a pulsatile and/or radio frequencysignal to the anatomical site from the control unit, the microsurgicaltool configured to convey one or more feedback signals related to thepulsatile and/or radio frequency signals back to the control unit. Inaspects, the feedback signals may be related to an electrode impedance,a bioimpedance, a local electrical field, or an electrophysiologicalresponse to the pulsatile and/or radio frequency signal.

In aspects, the stimulation and/or ablation electrode may be includedwithin the microsurgical tool, coupled to a microfinger, included in asensing tip, or the like.

In aspects, the control unit may be configured to sweep one or more ofthe sensing tips along the lumen wall, to use one or more of theelectrophysiological signals to locate the anatomical site, to use oneor more of the electrophysiological signals to exclude the anatomicalsite from a surgical procedure, combinations thereof, or the like.

According to aspects there is provided, a method for determining anafferent electrophysiological activity and an efferent physiologicalactivity in the vicinity of a lumen, including monitoringelectrophysiological activity at a plurality of sites within thevicinity of the lumen in regions proximal and distal to a target regionas measured along a length of the lumen, applying energy to a sitewithin the target region to form a neurological block thereby, andextracting an afferent signal from activity in the distal region and anefferent signal from activity in the proximal region.

In aspects, the method may include comparing activity measured in theproximal region and the distal region to determine if the energyapplication affected the electrophysiological activity in the vicinityof the target region. In aspects, the method may include evaluating thecoherence between activities measured in the proximal region and thedistal region and/or using the coherence to evaluate the extent of theneural block.

In aspects, the application of energy may be sufficient to form atemporary neuroblock (i.e. just sufficient to form a temporary block,controlled so as to form a temporary block, etc.). In aspects, themethod may include comparing activities from the proximal region and thedistal region during the temporary neuroblock and diagnosing aneurological condition, evaluating a neurological state, determining ifa permanent surgical procedure is required, combinations thereof, or thelike.

According to aspects there is provided, a method for evaluatingsympathetic tone of a subject, including inserting a microsurgical toolin accordance with the present disclosure into a lumen of the subject,recording the electrophysiological signals conveyed by the microsurgicaltool from a wall of the lumen, removing the microsurgical tool from thelumen, and generating a metric relating to sympathetic tone from therecorded signals.

In aspects, the method may include monitoring another physiologicparameter remotely from the lumen to generate a corrective signal andusing the corrective signal to remove movement artifacts from theelectrophysiological signals.

In aspects, the method may include stimulating one or more anatomicalsites in the subject during the recording, and/or diagnosing a medicalcondition based at least in part upon the metric.

According to aspects there is provided a method for monitoring and/orevaluating electrophysiological activity in the vicinity of a lumen,including biasing an electrode against a wall of the lumen; andrecording one or more electrophysiological signals from the activity inthe vicinity of the electrode.

In aspects, the method may include recording one or more of an evokedpotential, electrolyte or solute concentration, remote stimulation ofnervous activity, an electromyographic signal [EMG], a mechanomyographicsignal [MMG], a local field potential, an electroacoustic event,vasodilation, vessel wall stiffness, muscle sympathetic nerve activity(MSNA), central sympathetic drive (e.g. bursts per minute, bursts perheartbeat, etc.), tissue tone, nerve traffic (e.g. post ganglionic nervetraffic in the peroneal nerve, celiac ganglion, superior mesentericganglion, aorticorenal ganglion, renal ganglion, and/or related nervoussystem structures) in the vicinity of the lumen.

The method may include electrically isolating the electrode from acavity of the lumen, embedding the electrode into the wall of the lumen,sweeping the electrode along the wall of the lumen, generating a map ofelectrophysiological activity from the recordings obtained during thesweep, recording electrophysiological activity from a plurality ofelectrodes, cancelling one or more movement artifacts from therecordings, combinations thereof, or the like.

In aspects, the method may include biasing a mechanomyographic (MMG)sensing element against the wall of the lumen and recording amechanomyographic signal (MMG) from the activity.

According to aspects there is provided, a method for performingcontrolled neuromodulation in the vicinity of a lumen, includingmonitoring electrophysiological activity at one or more sites within thevicinity of the lumen to obtain a first activity level, applying energyto a treatment site within the vicinity of the lumen, monitoringelectrophysiological activity at one or more sites within the vicinityof the lumen to obtain a second activity level, and comparing the firstactivity level and the second activity level to determine if the energyapplication affected the electrophysiological activity, if sufficientenergy was applied, if further energy should be applied, combinationsthereof, and the like.

In aspects, the electrophysiological activity may relate to one or moreof an evoked potential, electrolyte or solute concentration, remotestimulation of nervous activity, an electromyographic signal [EMG], amechanomyographic signal [MMG], a local field potential, anelectroacoustic event, vasodilation, vessel wall stiffness, musclesympathetic nerve activity (MSNA), central sympathetic drive (e.g.bursts per minute, bursts per heartbeat, etc.), tissue tone, nervetraffic (e.g. post ganglionic nerve traffic in the peroneal nerve,celiac ganglion, superior mesenteric ganglion, aorticorenal ganglion,renal ganglion, and/or related nervous system structures) as measured inthe vicinity of the lumen.

In aspects, the method may include determining if sufficient energy hasbeen applied to the treatment site based on the comparison, evaluatingthe first activity level to determine a suitable treatment site in thevicinity of the lumen, mapping electrophysiological activity in thevicinity of the lumen using the first activity level, applying astimulus in the vicinity of the lumen, recording electrophysiologicalactivity before, during, and/or after the stimulus, or the like.

In aspects, the method may include recording electrophysiologicalactivity in a proximal region and a distal region measured along thelength of the lumen as spaced with respect to the treatment site, todetermine if the energy application affected the electrophysiologicalactivity in the vicinity of the treatment site, determining if theenergy application was sufficient to form a neural block using thecomparison, applying sufficient energy to the treatment site to form atemporary block and assessing if the change in electrophysiologicalactivity is desirable, if so, applying sufficient energy to thetreatment site so as to form a substantially irreversible block, or thelike.

In aspects, the energy may be provided in the form of a radio frequencycurrent, an ultrasonic wave, thermal energy, a neuroblocking agent,radiation, electromagnetic radiation, radiosurgically generatedradiation, combinations thereof, or the like.

In aspects, one or more of the steps of a method in accordance with thepresent disclosure may be performed using a surgical tool in accordancewith the present disclosure.

According to aspects there is provided a method for determining a stateof a neurological connection along a neurological pathway between one ormore regions in a body, including applying a pacing signal to a lumen inthe vicinity of the neurological pathway, monitoring one or more ofwater concentration, tone, blood oxygen saturation of local tissues,evoked potential, electrolyte or solute concentration,stimulation/sensing of nervous activity, electromyography, temperature,blood pressure, vasodilation, vessel wall stiffness, muscle sympatheticnerve activity (MSNA), central sympathetic drive (e.g. bursts perminute, bursts per heartbeat, etc.), tissue tone, blood flow (e.g.through an artery, through a renal artery), a blood flow differentialsignal (e.g. a significantly abnormal and or sudden change in blood flowwithin a structure of the body, a vessel, an organ, etc.), bloodperfusion (e.g. to an organ, an eye, etc.), a blood analyte level (e.g.a hormone concentration, norepinephrine, catecholamine, renin,angiotensin II, an ion concentration, a water level, an oxygen level,etc.), nerve traffic (e.g. post ganglionic nerve traffic in the peronealnerve, celiac ganglion, superior mesenteric ganglion, aorticorenalganglion, renal ganglion, and/or related nervous system structures), orcombinations thereof, or the like at one or more sites within the bodyto generate one or more physiological signals; and evaluating theinfluence of the pacing signal on the physiological signals anddetermining the state of neurological connection therefrom.

In aspects, the method may include applying energy in the vicinity ofthe lumen so as to induce a neurological block along the neurologicalpathway, pacing and monitoring before and after induction of theneurological block, and/or comparing the physiological signals obtainedbefore the neurological block to those obtained during the neurologicalblock to determine the influence of the neurological block there upon,combinations thereof, and the like.

In aspects, the method may include determining if the neurological blockis favorable in terms of treating an underlying disease state in thebody, and/or applying energy in the vicinity of the lumen so as toinduce a substantially permanent neurological block along theneurological pathway.

In aspects, the method may include monitoring electrophysiologicalactivity at a plurality of sites within the vicinity of the lumen inregions proximal and distal to the pacing site and/or to the site of asuspected or known neurological block.

In aspects, the method may include extracting an afferent signal fromactivity in the distal region and an efferent signal from activity inthe proximal region and/or comparing activity measured in the proximalregion and the distal region to determine if the energy applicationaffected the electrophysiological activity in the vicinity of the targetregion.

According to aspects there is provided, use of a method in accordancewith the present disclosure for evaluation of the effectiveness of aneuromodulation procedure within a body.

According to aspects there is provided, a system for alteringfunctionality of a neural structure in the vicinity of a lumen coupledto an organ of a subject, the system including a tool configured toapply a procedure to a first region in the vicinity of the lumen, and toapply a follow on procedure to a second region in the vicinity of thelumen, the second region being located equidistant or closer to theorgan than the first region, a sensor designed so as to be coupled tothe subject, configured to monitor one or more physiologic parametersfrom the subject, and a feedback system coupled with the sensor,configured to convey the outcome of the procedure to an operator basedupon changes in the physiologic parameter.

In aspects, the feedback system may be configured to indicate to theoperator a successful outcome for the procedure if the physiologicparameter does not substantially change during a predetermined periodfollowing application of the follow on procedure. In aspects, thefeedback system may be configured to indicate to the operator anunsuccessful outcome for the procedure if the physiologic parametersubstantially changes during a predetermined period followingapplication of the follow on procedure.

In aspects, the first region and/or the second region may substantiallysurround the circumference of the lumen (i.e. form a substantiallycylindrical, elliptical, flower-like shape, etc. surrounding the lumen).

Some non-limiting examples of procedures include an ablation, anexcision, a cut, a burn, a radio frequency ablation, freezing, amicrowave ablation, radiosurgery, an ultrasonic ablation, an abrasion, abiopsy, delivery of a substance, combinations thereof, and the like.

Some non-limiting examples of follow on procedure include an ablation,an excision, a cut, a burn, a radio frequency ablation, freezing, amicrowave ablation, radiosurgery, an ultrasonic ablation, an abrasion, abiopsy, stimulation, delivery of a substance, combinations thereof, andthe like.

In aspects, the physiologic parameter may be or may be related to one ormore of water concentration, tone, blood oxygen saturation of localtissues, evoked potential, electrolyte or solute concentration,stimulation/sensing of nervous activity, electromyography, temperature,blood pressure, vasodilation, vessel wall stiffness, muscle sympatheticnerve activity (MSNA), central sympathetic drive, a mechanomyographicsignal, a local field potential, an electroacoustic event, centralsympathetic drive, tissue tone, nerve traffic, heart-rate, heart-ratevariability, a combination thereof, or the like.

In aspects, the period may be longer than 5 seconds (s), longer than 30s, longer than 1 minute (min), longer than 3 min, longer than 5 min,longer than 8 min, or the like. In aspects, such a period may bedetermined during monitoring following a first procedure, the procedure,or the like. In one non-limiting example, the period may be determinedby performing a procedure, monitoring until a change in the physiologicparameter takes place, and timespan between the procedure and thechange. Then the period may be set to 1.1× the timespan, 1.5× thetimespan, 2× the timespan, etc.

In aspects, the timespan between application of the procedure and theapplication of the follow on procedure may be longer than 5 s, longerthan 30 s, longer than 1 min, longer than 3 min, longer than 5 min,longer than 8 min, or the like.

In aspects, the system may be configured to apply one or more subsequentfollow on procedures to the first region or second region of thesubject. In aspects, such subsequent follow on procedures may be appliedduring a follow-up, such as approximately 1 week after the procedure, 1month after, 3 months after, 6 months after, 1 year after, or the like.

In aspects, the feedback system may be configured to indicate to theoperator a durable outcome for the procedure if the physiologicparameter does not substantially change during a predetermined periodfollowing application of one or more of the subsequent follow onprocedures.

Some non-limiting examples of feedback generated by a feedback system inaccordance with the present disclosure include visual feedback, audiofeedback, indictors, a visual indicator, signal feedback, a tracing, anumerical readout, a pass/fail indicator, combinations thereof, and thelike.

In aspects, the system may include tool and/or a sensing tip inaccordance with the present disclosure, one or more portions of the tooland/or sensing tip electrically coupled to the feedback system, sizedand dimensioned so as to be deliverable to and to interface with thefirst region and/or the second region, the sensing tip configured tomonitor electrophysiologic activity in the vicinity thereof and toconvey a signal related thereto to the feedback system.

In aspects, the tool may include a balloon catheter, the ballooncatheter including a balloon with a surface, the balloon shaped anddimensioned for placement within the lumen, the balloon including one ormore energy and/or chemical delivery elements arranged along the surfacethereof, one or more of the energy and/or chemical delivery elementsconfigured to perform the procedure and/or the follow on procedure.

In aspects, the tool may include the sensor.

In aspects, the sensor may be a pressure sensor sized so as to fitwithin a lumen in the body, configured to measure a blood pressureresponse therefrom.

According to aspects there is provided, use of a system in accordancewith the present disclosure to perform a denervation and/orneuromodulation procedure within the vicinity of a lumen within thebody, within the vicinity of a renal artery, etc.

According to aspects there is provided, use of a system in accordancewith the present disclosure to assess the durability of a denervationand/or neuromodulation procedure.

According to aspects there is provided, a method for alteringfunctionality of a neural structure in the vicinity of a lumen coupledto an organ in a subject, including applying a procedure to a firstregion in the vicinity of the lumen, subsequently applying a follow onprocedure to a second region in the vicinity of the lumen, the secondregion being equidistant or closer to the organ than the first region,monitoring a physiologic parameter from the subject, and determining theoutcome of the procedure based upon the monitoring after the follow onprocedure.

In aspects, the outcome may be successful if the physiologic parameterdoes not substantially change during a predetermined period followingapplication of the follow on procedure. In aspects, the outcome may beunsuccessful if the physiologic parameter substantially changes during apredetermined period following application of the follow on procedure.

In aspects, some non-limiting examples of procedures include anablation, an excision, a cut, a burn, a radio frequency ablation,freezing, a microwave ablation, radiosurgery, an ultrasonic ablation, anabrasion, a biopsy, delivery of a substance, combinations thereof, andthe like.

In aspects, some non-limiting examples of follow on procedures includean ablation, an excision, a cut, a burn, a radio frequency ablation,freezing, a microwave ablation, radiosurgery, an ultrasonic ablation, anabrasion, a biopsy, stimulation, delivery of a substance, combinationsthereof, and the like.

In aspects, the physiologic parameter may be or be related to one ormore of water concentration, tone, blood oxygen saturation of localtissues, evoked potential, electrolyte or solute concentration,stimulation/sensing of nervous activity, electromyography, temperature,blood pressure, vasodilation, vessel wall stiffness, muscle sympatheticnerve activity (MSNA), central sympathetic drive, a mechanomyographicsignal, a local field potential, an electroacoustic event, centralsympathetic drive, tissue tone, nerve traffic, heart-rate, hear-ratevariability, a combination thereof, or the like.

In aspects, the period may be longer than 5 s, longer than 30 s, longerthan 1 min, longer than 3 min, longer than 5 min, longer than 8 min, orthe like.

In aspects, the method may include waiting between the application ofthe procedure and the application of the follow on procedure for longerthan 5 s, longer than 30 s, longer than 1 min, longer than 3 min, longerthan 5 min, longer than 8 min, or the like.

In aspects, the method may include applying one or more subsequentfollow on procedures to the first region and/or second region in thesubject.

In aspects, the outcome may be considered to be durable if thephysiologic parameter does not substantially change during apredetermined period following application of one or more of thesubsequent follow on procedures. In aspects, such subsequent follow onprocedures may be applied during a follow-up visit, such asapproximately 1 week after the procedure, 1 month after, 3 months after,6 months after, 1 year after, or the like.

In aspects, the method may include monitoring electrophysiologicalactivity in the vicinity of the first region or the second region, theoutcome related to changes therein. Such monitoring ofelectrophysiological activity may be provided by a tool, surgical tool,sensing tip, etc. in accordance with the present disclosure.

In aspects, one or more steps may be provided by a balloon catheter, theballoon shaped and dimensioned for placement within the lumen.

In aspects, one or more of the steps may be provided by an ultrasounddelivery system.

In aspects, the monitoring may be provided by a pressure sensor coupledto the subject.

According to aspects there is provided, a method for determining thedurability of a treatment of a neural structure in a first regionlocated in the vicinity of a lumen coupled to an organ in a subject,including applying a procedure to a second region in the vicinity of thelumen, the second region being equidistant or closer to the organ thanthe first region, monitoring a physiologic parameter from the subject,and determining the durability of the treatment based upon themonitoring after the procedure.

In aspects, the treatment may be considered to be durable if thephysiologic parameter does not substantially change during apredetermined period following application of the procedure. In aspects,the treatment may be considered to be not durable if the physiologicparameter substantially changes during a predetermined period followingapplication of the procedure.

In aspects, some non-limiting examples of procedures include anablation, an excision, a cut, a burn, a radio frequency ablation,freezing, a microwave ablation, radiosurgery, an ultrasonic ablation, anabrasion, a biopsy, stimulation, delivery of a substance, combinationsthereof, and the like.

According to aspects, there is provided use of a method in accordancewith the present disclosure for evaluation of the effectiveness of aneuromodulation and/or denervation procedure within a body.

BRIEF DESCRIPTION OF THE DRAWINGS

Several aspects of the disclosure can be better understood withreference to the following drawings. In the drawings, like referencenumerals designate corresponding parts throughout the several views.

FIGS. 1a-c show aspects of a tool tip (i.e. a surgical or interventionaltool tip) in accordance with the present disclosure in a delivery modeand a deployed mode.

FIGS. 2a-c show aspects of deployed surgical tips in accordance with thepresent disclosure interacting with a local surgical site.

FIG. 3 shows aspects of a plurality of micro-tips configured formonitoring physiological response and/or stimulating local tissue duringa surgical procedure in accordance with the present disclosure.

FIGS. 4a-b show aspects of interactions between multiple micro-tips anda lumen wall in accordance with the present disclosure.

FIGS. 5a-c show aspects of micro-tips in accordance with the presentdisclosure.

FIGS. 6a-b show aspects of a microfinger in accordance with the presentdisclosure.

FIGS. 7a-b show aspects of a micro-tip including a mechanomyographic(MMG) sensing element and a typical response in accordance with thepresent disclosure.

FIGS. 8a-b show aspects of a micro-tip in accordance with the presentdisclosure.

FIG. 9 shows aspects of a micro surgical tool deployed at a surgicalsite in accordance with the present disclosure.

FIGS. 10a-d show aspects of non-limiting examples of monitoring methodsin accordance with the present disclosure.

FIGS. 11 a-g show aspects of non-limiting examples of ablation patternsapplied to a lumen wall (i.e. an artery, a renal artery, etc.) inaccordance with the present disclosure.

FIGS. 12a-d show aspects of micro surgical tools in accordance with thepresent disclosure deployed at a surgical site.

FIG. 13 shows a schematic diagram of interaction between one or moremacroelectrodes and a micro surgical tool deployed at a surgical site inaccordance with the present disclosure.

FIG. 14 shows aspects of a micro balloon catheter deployed at a surgicalsite in accordance with the present disclosure.

FIGS. 15a-b show aspects of an array of optical microsensing tips and acollective response therefrom in accordance with the present disclosure.

FIG. 16 shows aspects of a combination catheterization and endoscopicprocedure on a renal artery in accordance with the present disclosure.

FIGS. 17a-c show aspects of micro surgical tools in accordance with thepresent disclosure.

FIGS. 18a-f show aspects of non-limiting examples of micro surgicaltools in accordance with the present disclosure.

FIGS. 19a-b show aspects of a tonal sensing micro-tip and sampleresponse in accordance with the present disclosure.

FIGS. 20a-b show aspects of surgical tools in accordance with thepresent disclosure.

FIG. 21 shows aspects of a system for performing a surgical procedure inaccordance with the present disclosure.

FIGS. 22a, b further illustrate aspects of systems and methods inaccordance with the present disclosure.

DETAILED DESCRIPTION

Particular embodiments of the invention are described hereinbelow withreference to the accompanying drawings; however, the disclosedembodiments are merely examples of the disclosure and may be embodied invarious forms. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as abasis for the claims and as a representative basis for teaching oneskilled in the art to variously employ the present disclosure invirtually any appropriately detailed structure. Like reference numeralsmay refer to similar or identical elements throughout the description ofthe figures.

A controlled nerve ablation system may include the capability to senseone or more physiologic parameters at one or more points around asurgical site, and/or include the capability to stimulate and/or ablatetissues at one or more of the same points and/or an alternative pointaround a surgical site. In aspects, the nerve ablation system may beconfigured so as to access a lumen, a vessel, very narrow vessels,and/or surgical sites in the body. The non-limiting examples disclosedherein are directed towards such configurations (e.g. so as tocontrollably ablate renal nerves along a renal artery with acatheterized procedure).

By lumen is meant a substantially hollow structure, with one or morewalls, enclosing a cavity. In the context of the present disclosure, alumen is generally considered elongate in shape, having a longitudinaldirection running along the length thereof, a radial direction runningsubstantially perpendicularly to a wall of the lumen, and acircumferential direction running substantially perpendicular to thelongitudinal direction along a wall of the lumen. In aspects, a lumenmay include a branch (a bifurication), a bend, a tortuous pathway, achanging diameter (i.e. a diameter that changes along the lengththereof), and the like. It is envisaged that a system in accordance withthe present disclosure may be apt at navigating such complicatedfeatures, thus providing therapy to a range of challenging to reachlocations.

The nerve ablation system may include one or more sensing tips (e.g. aslocated on a micro-tip, a wire, an electrode in a matrix, on a flexibleballoon, etc.). One or more sensing tips may include a pressure sensor,a tonal sensor, a temperature sensor, an electrode (e.g. to interactwith a local tissue site, provide a stimulus thereto, measure apotential therefrom, monitor current to/from the tissues, to measure abioimpedance, measure an evoked potential, electrolyte or soluteconcentration, an electromyographic signal [EMG], anelectrocardiographic signal [ECG], a mechanomyographic signal [MMG], alocal field potential, etc.), an acoustic sensor, an oxygen saturationsensor, or the like.

The sensing tips may be configured to elucidate a range of keyphysiological aspects before, during, and/or after a procedure. Thefollowing description outlines some non-limiting approaches in thisrespect. Such sensing tips may be integrated into one or moremicrofingers, micro-tips, flexible circuits, stretchable substrates,etc.

In aspects, one or more sensing tips in accordance with the presentdisclosure may be configured to monitor bioimpedance between one or moresensing tips to determine the degree of contact between the finger tipsand the anatomical site, and/or potentially the bias force between thefinger tips and the anatomical site. Additionally, alternatively, or incombination, bioimpedance measurements between one or more sensing tipsmay be useful in determining when adequate contact has been made as wellas how much current should be applied to an anatomical site during anablation procedure. Furthermore, additionally, alternatively, or incombination bioimpedance between one or more sensing tips may be used todetermine the status of tissue positioned there between. In onenon-limiting example, the bioimpedance spectrum between two or moresensing tips may be used to map the local tissue impedance. Suchinformation may be useful to elucidate where such tissue has beencompletely ablated, where tissue has yet to be ablated, etc.

In aspects, bioimpedance measurement between on or more sensing tips, asensing tip and a separate electrode, etc. may be used to determine astate of isolation between one or more of the sensing tips and a localfluid (i.e. to determine a state of isolation between a sensing tip andfluid within a lumen, between a sensing tip and blood, etc.).

In aspects, one or more sensing tips in accordance with the presentdisclosure may be configured to obtain mechanomyographic informationduring a procedure as determined by slight changes in an associatedstrain measurement, tip vibration, and/or contact force measurement(e.g. via direct force measurement between the tip and the localanatomy, and/or via changes in the deformation of the microfinger asmeasured by an associated micro strain gage attached thereupon).Mechanomyographic information may be related to local nervous activityeither naturally occurring or in response to a stimulus (e.g. optionallyapplied by one or more sensory tips, locally, remotely, during and/orvia a local RF pulse, etc.). In aspects, a sensing tip may include apiezoresistive strain gauge, a piezoelectric microtransducer, aninterfacial pressure sensing membrane or the like to detectmechanomyographic signals. In one non-limiting example, the sensing tipmay be coated with a micro or nano coating of a piezoresistive and orpiezoelectric material (e.g. a piezoelectric polymer, an electret, anano-particulate filled elastomer, a conjugated polymer, etc.). Inaspects, the mechanomyographic tip may be configured so as to measureone or more aspect of the tissue compliance of the local tissues (e.g.so as to identify calcified material, cancerous tissues, etc.).

In aspects, one or more sensing tips in accordance with the presentdisclosure may be configured to monitor an electrophysiological signal.Such electrophysiological monitoring at and/or between one or moresensing tips, may be used to map nervous response, electromyographicresponse (EMG), evoked potential, electrolyte or solute concentration,local field potential, extracellular field potentials, etc. along and/orwithin the wall of the local anatomical site (e.g. the wall of a lumen,a vessel wall, an artery wall, a venous wall, an organ wall, etc.). Suchinformation may be advantageous for selecting tissues on which toperform a surgical procedure (e.g. an ablation procedure, a biopsy,etc.), to follow and/or map a nerve along the length of the surgicalsite (e.g. along the wall of an artery, a vein, a tubule, etc.), todetermine the state of a surgical procedure, etc. In aspects, one ormore sensing tips may be configured to monitor a local electromyographic(EMG) signal before, during and/or after a surgical procedure as a meansfor monitoring local nervous activity. In such aspects, the EMG signalsmay be used as feedback for monitoring the extent of a denervationprocedure.

In aspects, one or more sensing tips in accordance with the presentdisclosure may be configured to monitor the tone of a tissue within abody. Monitoring the tone (e.g. mechanical properties, wall stiffness,elastic spectral response, mechanical impedance, physiologic properties,etc.) of the adjacent tissues may be determined by combining strainand/or force measurement of the sensing tips while applying movement(optionally cyclical or oscillatory movement) to one or more sensortips. Such sensing tips may be excited locally (e.g. such as by a localpiezoelectric transducer, a capacitive transducer, an electrochemicaltransducer, a smart material, etc.) or globally (e.g. such as byoscillatory torsional oscillations, axial oscillations, linearoscillations of the surgical tool tip, the associated guide wire,catheter, etc.).

In aspects, one or more of the sensing tips may be interfacedasymmetrically with the associated tissues (i.e. with a bent tip, amicro finger, a wire-like finger configured substantially parallel tothe tissue surface, oriented at an acute angle thereto, etc.). Byasymmetrically is meant such that the sensing tip approaches theassociated tissue surface at an angle other than perpendicular thereto.To describe the use of such a tip to monitor local tissue tone and/orfor providing a controlled interfacial force before, during and/or aftera procedure, for purposes of discussion, a clockwise torsion may be usedto advance the sensing tip along the surface of the local tissues and arelatively small counterclockwise torsion may be used to measure thetone of adjacent tissues. By relatively small is meant an excitationthat is sufficiently small in amplitude such that the sensing tip maynot appreciably slide along the tissue surface. In aspects, one or moresensory tips, in a structure attached thereto, and/or a system inaccordance with the present disclosure may include a vibratory excitermay be configured to generate the excitation.

In aspects, such a tone monitor may be combined with interfacial contactsensing, electrophysiological measurement, and/or sensor tip strainmeasurement in order to generate a wealth of local tissue informationbefore, during, and/or after a surgical procedure. In one non-limitingexample, the local tissues may stiffen during an ablation procedure. Bymonitoring local tissue tone, a stiffness level may be used tocharacterize when a suitable degree of ablation has been applied so asto irreversibly damage the tissues. Monitoring of a local tissue tone,perhaps at a monitoring site significantly removed from the surgicalsite such that the surgical procedure does not directly affect tissuesin the vicinity of the monitoring site (i.e. does not directly cut,heat, ablate, abrade, the tissues, etc.) may also be advantageous fordetermining an effect of the surgical procedure on one or morephysiologic parameters of a tissue (e.g. a vessel wall stiffness, changein nerve activity, change in blood perfusion, etc.) adjacent to themonitoring site.

In aspects, such tone measurement may be useful in determining the localstiffness of tissues (and/or overall wall stiffness of an adjacentvessel, organ, etc.) in contact with a sensing tip array (e.g. so as todetermine the type of tissue adjacent to one or more sensing tips,locate plaque, locate a cancerous tumor, etc.). Tone measurement mayfurther be used to characterize the type of tissue with which the tip isinterfacing (e.g. muscle, nervous tissue, fat, plaque, cancerous tissue,etc.). In aspects, such information, possibly in combination withbioimpedance data, electrophysiological monitoring, or the like, may beused to determine how much RF energy to apply locally during an RFablation procedure.

In one non-limiting example of a method for RF ablating tissue, thelocal tissue tone may be measured before, during, between individual RFpulses, and/or after a train of RF pulses. As the local tissue tonechanges during application of the RF pulses, the tonal changes may beused to determine the extent of the therapy. As the RF ablation processis applied to the adjacent tissues (perhaps via one or more sensingtips), the tonal measurements (as determined by one or more sensingtips, perhaps the same tip through which the RF signal may be applied)may be monitored as the tonal measurements may not be significantlyaffected by the local RF currents.

In aspects, electrophysiological stimulation and/or sensing from one ormore sensing tips in a sensing tip array, or a system in accordance withthe present disclosure may be used to interface with, monitor and/orstimulate nervous function within a local anatomical structure (e.g. alumen wall, a vessel wall, along a nerve, an organ wall, a duct, etc.).Such information may be used to hunt for target tissues (e.g. nerves),select tissues for a surgical procedure, to determine the degree ofprogression of a surgical procedure (e.g. a degree of ablation during RFsurgery, etc.).

In aspects, an array of sensing tips may be configured to apply adirectional stimulation and/or multi-site sensing so as to selectivelytreat/monitor only nerves that are configured to send signals in thepreferred direction (e.g. to selectively target primarily efferent nervebundles, afferent nerve bundles, etc.). Such a configuration may beadvantageous for treating a neurological disorder with minimal impact tothe surrounding anatomy and physiologic function of the associatedorgans.

In aspects, one or more sensing tips in accordance with the presentdisclosure may include the capability to apply/receive an RF currentto/from the surrounding tissue. The RF current may be provided locallybetween two of more sensing tips, or alternatively between one or moresensing tips and a macroelectrode placed elsewhere on the body (e.g. ona large skin patch over the surgical site, as selected from multiplepatches placed over the body, etc.). In a non-limiting example wherecurrent is restricted to being applied between sensing tips, the pathfor current flow may be well controlled, yet may be highly localized.Alternatively, in an example where RF current is passed between one ormore sensing tips and one or more macroelectrodes, the direction ofcurrent flow may be more challenging to control, but may be used toaccess tissues more remote from the sensing tips (i.e. farther into theadjacent tissues, deeper into an organ, farther from a lumen wall,etc.).

In aspects, network impedance measurements between one or more sensingtips and one or more macroelectrodes (e.g. as attached to the body ofthe patient), may be monitored prior to and/or during application of anRF ablation current. Each sensing tip and/or macroelectrode may includean impedance control circuit that may be adjustable such that theoverall current flow through the network formed from all the elements iscontrolled there through. Such a configuration may be advantageous tomore precisely control the local ablation process, thus targeting thelocal tissues with more accuracy, precision, spatial discrimination, andconfidence than less controlled approaches.

In another non-limiting example, a plurality of sensing tips may beengaged with the flow of RF current during an ablation process. Inaspects, the local impedance of each microfinger and/or sensing tip maybe monitored and/or controlled so as to better optimize the currentdelivered thereto. Additionally, alternatively, or in combination, thelocal current flow through each sensing tip may be monitored so as todetermine the path of the RF current flow, to ensure no leakage currentsare detected, etc. Such information may be used to more preciselycontrol the delivery of RF currents to the local anatomy during anablation procedure.

Additionally, alternatively, or in combination, before, during and/orafter the RF current is applied to the surrounding tissues, one or moresensing tips may monitor a physiologic parameter (e.g. waterconcentration, tone, blood oxygen saturation of local tissues, evokedpotential, electrolyte or solute concentration, stimulation/sensing ofnervous activity, local field potential, extracellular activity, EMG,temperature, etc.) to determine the extent of completion of the intendedsurgical procedure.

In aspects, one or more sensing tips may include an optical microsensor(e.g. a micropackage including a light source and/or a CMOS photosensor)and/or a fiber optic element. During a surgical procedure, the opticalmicrosensor may be positioned against or near to the local tissues foranalysis before, during and/or after an ablation procedure.

In aspects, an optically configured sensing tip (or group of tips) maybe configured to locally assess blood perfusion and/or blood oxygenationin the tissues adjacent thereto. The system may be configured toautomatically adjust and/or halt the surgical procedure based uponchanges in this signal. Alternatively, additionally, or in combination,the system may alert a user (e.g. a surgeon, an attendant, etc.) to achange in this signal before, during, and/or after a surgical procedure.Such a configuration may be useful for assessing local tissue healthbefore, during, and/or after a surgical procedure, the extent of asurgical procedure, etc.

In another non-limiting example, one or more optically configuredsensing tips may be configured so as to be biased towards the tissues ofa lumen, a vessel, or the like in the vicinity of the surgical site. Theoptical sensing tips may include one or more light sources (e.g. lightemitting diodes, fiber optic tips, etc.) configured to deliver narrow,multiband, and/or wideband light to the adjacent tissues. In aspects,one or more of the optical sensing tips may include one or morephotodetectors (e.g. a photodetector, a phototransistor, a fiber optictip, etc.) to receive and/or analyze the light reflected from theadjacent tissues. The received light may be related to that emitted byone or more of the light sources, or may be received from an ambientlight source, perhaps located to the exterior of the vessel, or theexterior of the subject's body.

The sources may be configured to emit light at predetermined wavelengthssuch that different absorption characteristics of the adjacent tissues,perhaps dependent on the wavelengths, may be observed during thesurgical procedure. The photodetectors may be configured to receive atleast a portion of this light, so as to assess the absorptioncharacteristics with the system (perhaps via a pre-amplification systemin accordance with the present disclosure, in an attached electronicsunit, etc.). The photodetected signals may be used to determine anoximetry value or a signal related thereto.

In one non-limiting example, the optically configured sensing tips maybe biased towards a site on the vessel wall before, during, and/or afterthe surgical procedure. Alternatively or in combination, the opticallyconfigured sensing tips may be substantially stationary with respect tothe vessel wall (such as via being attached to a collar of known size,attached to a structure of known width, as part of a structure that isexpanded to a known radius, etc.). In aspects, the magnitude of the biasmay be controlled by sensors and actuators both accordance with thepresent disclosure. Changes in the optical signals detected by thephotodetectors (perhaps due to changing bias force) before, duringand/or after a surgical procedure may be related to changes in the biasforce with which they are held against the vessel wall. Such aconfiguration may be advantageous for determining a change insympathetic tone and/or vasodilation before, during and/or after asurgical procedure.

In one non-limiting example, the optically configured sensing tips maybe coupled with one or more strain and/or interfacial force measurementmethods, perhaps to give a more precise reading of the bias forcebetween the sensing tip(s) and the adjacent tissues, to compensate formovement related artifacts, or the like.

In aspects, one or more of the optical sources may be selected such thatthe penetration of the light into the adjacent tissues may becontrolled. In one non-limiting example, a blue wavelength and a redwavelength may be emitted into the tissues. The blue wavelength mayprovide information relating to the deformation and absorption near tothe surface of the tissues, while the red wavelength may penetrate moredeeply into the adjacent tissues, providing a signal that changes inresponse to deformation of tissues farther from the contact site(s)between the tip(s) and the tissue. The photodetectors or equivalentoptical detection pathway may include filters, polarized windows, or thelike to separately assess the different spectra during an analysis.Comparison between photodetected signals in the blue spectrum with thoseobtained from the red spectrum may be used to determine tone and/orelastic modulus of the tissues of the vessel in the vicinity of thesensing tip(s). Such a configuration may be advantageous for assessingsympathetic tone (i.e. via muscular tension measurement), and/orvasodilation, vessel wall stiffness, and/or local tissue stiffnessbefore, during and/or after a surgical procedure. Changes in suchproperties may be indicative of the degree of completion of the surgicalprocedure.

In aspects, an externally placed (e.g. onto the body of the subject)light source (e.g. infrared, near infrared, visible, etc.) may bedirected into the body towards the surgical site. The light source mayoptionally be modulated to provide a more easily detected signal withinthe subject. One or more sensing tips equipped with optical microsensorsmay sense light emitted from the light source. The mapping of receivedlight may be used to locate and/or localize one or more anatomicalfeatures such as nerves near to one or more of the optical microsensorequipped sensing tips.

In aspects, one or more externally placed light sources may be used tohelp locate the anatomical sites of interest during the procedure. Anexternal light source may include a narrow band light source, a broadband light source, light sources spaced apart from each other, and/orcombinations thereof. The light sources may be modulated so as to bemore easily detectable by sensors located on, in, or near to the anatomyof interest. In one non-limiting example, a plurality of light sourcesmay be aimed at the surgical site from distinct vantage points withinthe body (i.e. as accessed via an endoscopic procedure, etc.) orexternally to the body (i.e. as positioned at locations on the body).

In another non-limiting example an endoscopic camera may be placed nearto the anatomy, lumen wall, and/or surgical site during a procedure toobserve both the anatomy, as well as placement of the surgical tools inthe vicinity of the anatomy. In one non-limiting example, the endoscopiccamera and/or light source may provide a suitable macroelectrode for RFablation processes performed during the surgical procedure.

In another non-limiting example, one or more sensing tips may beequipped with a corresponding micro-light source (e.g. an oLED, an LED,etc.). The micro-light source may be used to direct light into theadjacent tissues. One or more sensing tips equipped with opticalmicrosensors may be configured to detect light emitted from themicro-light source as back scattered by the adjacent tissues. Suchinformation may be used to detect anatomical features (e.g. nerves,tumors, etc.) in the adjacent tissues.

Such optical configurations may be advantageous for mapping the localtissues before, during and/or after a surgical procedure. They may alsobe advantageous for implementation into a nerve detection system (e.g.perhaps as input to a nerve hunting algorithm, etc.).

In one non-limiting example, the system may include a micro ballooncatheter for placement into a vessel (e.g. a renal artery, etc.). Themicro balloon catheter may be coated with a thin layer of an indicatormolecule. The indicator molecule may be tagged to attach to the targettissue of interest and/or tagged so as to change chromatic propertieswhen bound to the target tissue (e.g. nervous tissue, etc.). Themolecules may be delivered to the desired tissues during a ballooncatheterization procedure. During such a procedure, the micro ballooncatheter may be placed into the vessel of interest and inflated so as tokiss the walls of the vessel. While in contact with the vessel walls,the indicator molecules may attach and migrate/diffuse into the localtissues. Such a procedure may be performed as a first surgical step oras combined with other aspects in accordance with the presentdisclosure. In aspects, the balloon may also be configured to deliver atherapeutic agent (i.e. a neuroblocking agent, ethyl alcohol, botulinumtoxin, etc.) to the anatomy of interest.

In a method in accordance with the present disclosure, one or moresensing tips are inserted into a lumen with a wall within a body andbiased towards the wall of the lumen, and one or moreelectrophysiological signals obtained therefrom. Theelectrophysiological signals may be analyzed to locate one or moretarget tissues for a surgical procedure (i.e. one or more sympatheticnerves, parasympathetic nerves, etc.). A bolus of therapeutic agent, anRF current, a thermal energy source, and/or the like may be delivered tothe identified tissues so as to perform the surgical procedurethereupon. In aspects, one or more post-procedural electrophysiologicalsignals may be analyzed to determine the extent of the surgicalprocedure.

In aspects, the therapeutic agent may be provided via a micro ballooncatheter in accordance with the present disclosure. In aspects, thetherapeutic agent may be delivered via one or more microfingers inaccordance with the present disclosure.

In aspects, the micro balloon catheter may include one or more sensorytips (e.g. in the form of functional elements attached to the balloon,attached to a superstructure surrounding the balloon, etc.) inaccordance with the present disclosure.

In aspects, the bioimpedance and/or electrophysiological signals betweenone or more sensing tips in the array and one or more sensing tips inthe array, an external electrode, a reference electrode, or the like maybe used to determine changes in the structure of the adjacent tissuesduring an ablation procedure. Such information may be useful indetermining the extent of the ablation procedure, char accumulation,etc.

In aspects, bioimpedance measurements may be correlated with nervedamage data, perhaps obtained during prior surgeries, development of theprocedure, and/or obtained during specific testing procedures, such thatchanges in local bioimpedance data may be used during a surgicalprocedure to determine the extent of the ablation procedure. Such aconfiguration may be advantageous in the case that the surgicalprocedure itself overwhelms the local electrophysiological activity tothe extent that neurological monitoring may be hindered for a prolongedperiod of time after the procedure has been completed.

In aspects, one or more sensing tips may be configured to monitor localelectrical fields during an ablation procedure in accordance with thepresent disclosure in order to better determine the current flow paththrough the adjacent anatomy, perhaps connected to a warning system toindicate to an operator when the ablation field is insufficient forachieving the intended goal. Such a configuration may be advantageousfor avoiding unnecessary damage to the tissues during a misfired ormisdirected ablation session.

In aspects, a system in accordance with the present disclosure mayinclude a micro balloon catheter including one or more sensory tips(e.g. in the form of functional elements attached to the balloon,attached to a superstructure surrounding the balloon, etc.). The microballoon catheter may be configured so as to bias the sensory tipsagainst the adjacent vessel walls, thus providing a reliable interfacefrom which selective ablation and detection processes may be performed.Such a micro balloon catheter may be advantageous for single placementtype surgical procedures in accordance with the present disclosure.

In aspects including a plurality of sensing tips (e.g. as placed onto amicro balloon catheter, a microfinger array, a microtool set, a flexiblecage assembly, etc.) the sensing tips may be interconnected with eachother, with signal processing circuitry, a local control circuit, andthe like and/or combinations thereof. In order to substantially reducethe number of signal wires that must be sent to the surgical site duringthe procedure, the networked array of sensing tips may be multiplexedtogether with a locally placed control circuit (e.g. an applicationspecific integrated circuit, distributed/interconnected circuitelements, a collection of flexible semiconducting circuit elements,etc.). The control circuit may be configured to communicate such signalswith an extracorporeal system (e.g. a computer, a control system, an RFablation controller, a data acquisition system, etc.). The controlcircuit may be configured to communicate with the extracorporeal systemvia analog and/or digital means and/or methods. In one non-limitingexample, the communication may be of primarily digital means such thatthe control circuit may exchange data pertaining to any sensing tip inthe array, as well as switch data, control data, RF pulse routing, etc.

In another non-limiting example, the networked array of sensing tips maybe interconnected with distributed electronic elements and flexibleelectrical interconnects (e.g. as applied to a balloon wall, as providedby structural wires, microfingers, wire mesh elements, etc.). Inaspects, one or more of the sensing tips, microfingers, or the like maybe included upon a flexible or stretchable electronic substrate, theelectronic substrate configured to interface the sensing tips with theanatomy as well as to electrically connect one or more sensing tips, orthe like with a controller, a control system, an operator, a graphicaluser interface, a display, or the like.

A controlled nerve ablation system in accordance with the presentdisclosure may include one or more microfingers.

To this effect, a microfinger array microsurgical tool is disclosedherein. Any element in the microfinger array may include a sensing tipin accordance with the present disclosure to interact with the localanatomy during a surgical procedure.

The microfinger array may be advantageous for accessing very smallanatomical sites within a body, perhaps through tortuous vessels, deepinto an organ, etc.

A microfinger array may be arranged in a surgical tool in accordancewith the present disclosure such that one or more of the microfingersmay substantially independently interface with the adjacent tissues.Thus if an array of microfingers is placed against a rough or otherwiseuncontrolled surface, each microfinger may be able to contact, maintaina controlled bias force against, substantially embed an associatedsensing tip into, and/or substantially maintain contact with the surfaceduring use, even if the microfinger array is dragged along the surfaceas part of a procedure, during movement of the surface, etc. Suchindependently adjustable microfingers may be advantageous so as tomaintain a known interfacial pressure, especially while monitoring,stimulating and/or ablating the tissue with the microfingers. Suchindependently adjustable microfingers may be advantageous tosubstantially embed an associated tip (i.e. an associated sensory tip)into an adjacent tissue during a procedure.

By microfinger is meant a substantially curved finger like member (i.e.with curvature at one or more points along the length thereof, withmulti-axial curvature, etc.). Such microfingers may generally have acharacteristic width (although may be of any cross sectional makeup).The microfingers may generally have characteristic widths on the orderof approximately 1 mm, 0.5 mm, 0.1 mm, 0.05 mm, 0.01 mm, or the like. Inone non-limiting example, one or more microfingers may include a Nitinolstructure (e.g. a wire, a ribbon, etc.) with characteristic width ofapproximately 50 um.

In aspects, one or more regions of a microfinger in accordance with thepresent disclosure may be selectively coated with an isolation layer(e.g. an oxide layer, a dielectric coating, a polymer layer, alubricious layer, etc.). In aspects, such an isolation layer may beselectively applied to regions of the microfingers (i.e. so as to createisolated regions and sensitive regions thereof).

In aspects, the microfingers may be configured so as to deploy and/orbias against one or more adjacent tissues during a procedure and may beused to contact ably sweep the local anatomy, for purposes of sensingand/or ablating during a surgical procedure. In aspects, one or moremicrofinger dimensions and structure may be designed so as to providesubstantially uniform and predictable bias forces on the adjacenttissues over a wide range of movements and dimensional variation.

In aspects, an array of microfingers in accordance with the presentdisclosure may be configured so as to sufficiently collapse down into adelivery catheter while expanding radially outwards upon deployment soas to form a controllably biased contact within a tubular anatomicalstructure (e.g. an artery, a vein, an intestinal wall, etc.).

In aspects, one or more microfingers in accordance with the presentdisclosure may be configured into the shape of a wire basket, amesh-like structure, or the like. In aspects, one or more regions ofsuch microfingers may be patterned with an isolation layer, so as todirect signals over the microfingers, towards associated sensing tips,to provide communication between associated sensing tips and controlelectronics, to control one or more mechanical properties thereof, orthe like.

Such a configuration may be advantageous for accessing tight anatomicalspaces of interest (e.g. small vessel walls), while also maintainingconsistent contact forces at a surgical site during a procedure,substantially embedding one or more sensory tips into a lumen wall,substantially isolating one or more sensing tips from an adjacent fluid,or the like.

In aspects, a microfinger array in accordance with the presentdisclosure may include a plurality of fingers, one or more such fingersconfigured to interface with the surrounding tissues and biased radiallyoutwards from a deployment site (e.g. a guide wire, a catheter, etc.).In aspects, the microfinger array may be deployed via longitudinalretraction of a restraining shell (i.e. a restraining layer in thecatheter), via application of heat or current (i.e. in the case of ashape memory microfinger, etc.), via projection of the microfinger arrayout of a delivery catheter (i.e. by advancing the microfinger arraybeyond the tip of the delivery catheter, etc.).

In aspects, one or more microfingers may include a spring-like wireelement (e.g. Nitinol, spring steel, etc.) and/or may include compositestructures including a spring-like element to provide a bias force so asto push the tip and/or one or more regions of the microfinger towardsthe wall of a vessel into which it is placed (i.e. towards a surface, alumen wall, a vessel wall, etc.).

In aspects, a microfinger may include a Nitinol structure, optionallyconfigured for passage of current flow, to and from the surroundingtissues, and/or communication of electrophysiological informationbetween an associated sensing tip and a connected microcircuit. Inaspects, the Nitinol structure may be configured such that, when an RFpulse is applied there through towards the surrounding tissues, theNitinol structure may retreat from the tissues after a predeterminedamount of energy has passed there through, upon reaching a predeterminedtemperature, or the like. Thus the Nitinol structure may provide aninherently controlled method for applying a quantum of RF energy to thesurrounding tissues. Such a configuration may be adapted for usesimultaneously, additionally, alternatively and/or in combination withone or more of the other aspects described in this disclosure.

In aspects, each finger in the array may move somewhat independently ofthe others such that all fingers may maintain contact with the vesselwall during a procedure.

Such a configuration may be advantageous for maintaining robust contactwith the walls of a tortuous anatomical site (e.g. a plaque filledartery, a tortuous vein, a damaged vessel, etc.) within the body. Such aconfiguration may be advantageous for maintaining robust contact withthe walls of a lumen, surgical site, etc. while performing a procedure(i.e. scanning a surface with one or more microfingers, dragging amicrofinger along a surface, monitoring a tissue site, ablating a tissuesite, etc.) or during periods of relative movement (i.e. in the presenceof organ movement, perhaps due to physiologic processes, stressesrelated to biorhythms, breathing, blood pressure, etc.).

In aspects, at least a portion of the microfingers may be formed asspirals such that torsion applied at the operator end of the cathetermay rotate the microfingers about the central axis of the lumen (i.e.blood vessel, etc.), thus allowing one to sweep the contact of themicrofingers around the entirety of the vessel interior. Such movementsmay be advantageous for analyzing the adjacent tissues, selectivelymapping and ablating the tissues, etc. In one non-limiting example, amicrofinger array in accordance with the present disclosure may be sweptcircumferentially along the wall of a vessel, optionally starting andstopping so as to analyze the local tissues. If a suitable site forablation is detected, the microfinger array may be used to ablate thetissues as well as monitor the ablation process to ensure controlledablation is achieved before continuing with the sweeping procedure.

In aspects, the microfingers may be formed slightly off axis, such thatrelative axial movement of an overlying sheath may be used to retractthe microfingers into the sheath or conversely to deploy them towardsthe anatomical site. Additionally, alternatively, or in combination, offaxis arrangements may provide the capability to sweep the microfingerscircumferentially along the anatomical site via applying torsion to theguide wire, delivery wire, and/or catheter to which they are attached.

Such a configuration may be advantageous for simultaneously mapping andselectively ablating an anatomical site during a surgical procedure.

Furthermore, such a configuration may be advantageous for working uponan anatomical site, while maintaining flow of fluid there through (i.e.as opposed to an occlusive tool, which may block flow during expansionthereof).

In aspects, one or more microfingers may be provided with highlyminiaturized and flexible structure so as to more easily access highlyrestricted anatomical sites within the body.

In aspects, one or more microfingers may include one or more sensingtips in accordance with the present disclosure for capturing informationfrom the local surgical site. Some non-limiting examples of sensingoptions include temperature sensors, electrodes, strain gauges, contactforce sensors, combinations thereof, and the like. For purposes ofdiscussion, a sensing tip may also be referred to as a microsensor.

The sensing tips may be configured to elucidate a range of keyinformation during a procedure. Some non-limiting examples are discussedin more detail below.

Bioimpedance between one or more microfinger tips may be used todetermine the degree of contact between the finger tips and theanatomical site, as well as potentially the bias force between thefinger tips and the anatomical site. Such information may be useful indetermining when adequate contact and to gauge how much current shouldbe applied to an anatomical site during an ablation procedure.

Mechanomyographic information may be obtained from fingertips during aprocedure as determined by slight changes in an associated strainmeasurement and/or contact force measurement (e.g. via direct forcemeasurement between the tip and the local anatomy, and/or via changes inthe deformation of the microfinger as measured by an associated microstrain gage attached thereupon).

Evoked potential monitoring at or between one or more finger tips, maybe used to map nervous response, electromyographic response,extracellular potentials, local field potentials, evoked potential, etc.along the wall of the local anatomy (e.g. vessel wall, organ wall,etc.). Such information may be advantageous for selecting tissues onwhich to perform a surgical procedure (e.g. an ablation procedure, abiopsy, a stimulation procedure, etc.).

The tone of the adjacent tissues may be determined by combining strainand/or force measurement of the microfingers while applying anexcitation to one or more microfingers (e.g. optionally clockwisetorsion to advance the microfingers and small counterclockwise torsionto measure the tone of adjacent tissues, a vibratory exciter incombination with contact and/or microfinger strain measurement, etc.).

Such tone measurement may be useful in determining the local stiffnessof tissues in contact with the microfinger array (e.g. so as todetermine the type of tissue adjacent to one or more microfingers, tolocate plaque, to locate a cancerous tumor, etc.).

Stimulation and sensing from one or more microfingers in the microfingerarray may be used to elicit nervous function of local anatomy. Suchinformation may be used to select tissues for a surgical procedure, todetermine the degree of progression of a surgical procedure (e.g. adegree of ablation during RF surgery, etc.). Directional stimulation andsensing may be used to selectively treat only nerves that are configuredto send signals in the preferred direction (i.e. via combination ofstimulation and/or sensing from a plurality of sensing tips, sensingsites, etc.).

In aspects, one or more microfingers may include the capability toapply/receive an RF current to/from the surrounding tissue.

Such RF currents may be applied between one microfinger in the array andan (optionally) distant counter electrode, between two or moremicrofingers in the array, to a extracorporeal patch on the body, etc.

In aspects pertaining to multiple microfinger RF current passage, thelocal impedance of each microfinger may be altered so as to control thecurrent delivered thereto.

In aspects pertaining to multiple microfinger RF current passage, thelocal current flow through each microfinger may be monitored so as todetermine the path of the RF current flow, to ensure no leakage currentsare detected, etc. Such information may be used to more preciselycontrol the delivery of RF currents to the local anatomy during anablation procedure.

In aspects, prior to, during, and/or after the RF current is applied tothe surrounding tissues, one or more microfingers may be configured tomonitor a physiologic parameter (e.g. water concentration, tone, bloodoxygen saturation of local tissues, evoked potential,stimulation/sensing of nervous activity, emg, temperature, etc.) todetermine the extent of completion of the intended surgical procedure.

In aspects, the bioimpedance between one or more microfingers in thearray may be used to determine changes in the structure of the adjacenttissues during an ablation procedure. Such information may be useful indetermining the extent of the ablation procedure, char accumulation,etc.

In aspects, bioimpedance measurements may be correlated with nervedamage data, perhaps obtained during prior surgeries or obtained duringspecific testing procedures, such that changes in local bioimpedancedata may be used during a surgical procedure to determine the extent ofthe procedure. Such a configuration may be advantageous in the case thatthe surgical procedure itself overwhelms the local electrophysiologicalactivity to the extent that neurological monitoring may be hindered fora prolonged period of time after the procedure has been completed.

In aspects, one or more microfingers may be configured to monitor localelectrical fields during an ablation procedure in order to betterdetermine the current flow path through the adjacent anatomy, perhapsconnected to a warning system to indicate to an operator when theablation field is insufficient for achieving the intended goal, toassist with the direction of energy towards the intended surgical site,to conserve energy, etc. Such a configuration may be advantageous foravoiding unnecessary damage to the tissues during a misfired ablationsession.

A system may include an embolic net to capture char that may form duringthe ablation procedure. Such netting may be advantageous for preventingsurgically related emboli from traveling throughout the body after thesurgery.

In aspects, the system and/or microfingers may include a coolantdelivery system (e.g. a saline delivery system) in order to cool themicrofingers during and/or after an ablation procedure. Such coolantdelivery may be advantageous for minimizing char and excessive damageassociated with an ablation procedure. Such coolant delivery may be partof a cryogenic surgical procedure, or the like.

In aspects, the system may include multiple microfinger arrays, perhapslocated at specific radii from each other such that when sweeping atubular anatomical site (e.g. a vessel), the bias forces may bereasonably maintained between the microfingers and the tissue walls.

In aspects, one or more microfingers may include an exposed electrodearea (i.e. as part of an electrode based sensing tip) that only touchesthe walls of the adjacent anatomy. Such a configuration may beadvantageous for minimizing current flow into the adjacent fluids withinthe vessel, to better control RF current flow in the vicinity of theelectrodes, minimize conductivity between the exposed area and thesurrounding fluid, so as to substantially embed the exposed electrodearea in to the wall of the adjacent anatomy, etc.

In aspects, one or more microfingers may include one or more activematerial elements. Control signals delivered to the active materialelement may help to bias the microfingers towards the intended surgicalsite, actively control the contact forces between finger tips and thesurgical sites, etc. Some non-limiting examples of active materials thatmay be suitable for application to one or more microfingers includeshape memory materials (e.g. shape memory alloys, polymers, combinationthereof), electroactive polymers (e.g. conjugated polymers, dielectricelastomers, piezoelectric polymers, electrets, liquid crystals, graftelastomers, etc.), piezoceramics (e.g. amorphous piezoceramics, singlecrystals, composites, etc.). In addition the active material may be usedas a vibratory exciter and/or mechanical probe, for use in monitoringthe tone of the adjacent tissues (see above), alternatively, in additionor in combination, to cause vibratory/ultrasonic ablation and/or localheating to the tissues. In such aspects, the active material may beincluded along the length and/or over a region of the microfinger (i.e.so as to influence the shape of the microfinger during contraction orexpansion of the active material).

In aspects, one or more microfingers may include an electrical shieldsuch that the microfinger tips are effectively shielded from othercurrents flowing through an associated catheter, the body, etc. during aprocedure.

In aspects, one or more elements of a microfinger based catheter mayinclude a bidirection switching network, micro amplifier array, asensory front end, combinations thereof, or the like in order to amplifysensed signals as close as possible to the anatomical interface, toswitch the function of a microfinger tip between sensory, stimulatory,and/or ablative functions, perform combinations thereof, or the like. Inaspects, the circuitry may be included in the delivery wire within thecatheter of the system. In such aspects, the circuitry may be coupled toone or more microfingers and/or sensing tips each in accordance with thepresent disclosure, and a secondary signal acquisition circuit, adigital communication block, a controller, an RF signal generator,combinations thereof, and the like.

In aspects, a bidirectional switching network may be used to enablebifunctional stimulation/sense capabilities in one or more microfingers,etc. The switching network may be included in a local amplifier array,as a flexible circuit, or silicon die interconnected to or placed uponone or more microfingers, etc. Alternatively, additionally, or incombination, an extracorporeal circuit element may be coupled to theswitching network and/or microfingers, sensing tips, etc. and to acontroller included within a surgical system including a microfingerarray in accordance with the present disclosure.

In aspects, a micro amplifier array may be used to preamplify thesignals obtained from one or more sensory aspects of the microfingers,so as to improve the noise signature, etc. during use. Themicroamplifier may be coupled to the catheter, embedded into thecatheter, embedded into one or more microfingers, etc.

In aspects, one or more microfingers in accordance with the presentdisclosure may be provided such that they are sufficiently flexible soas to buckle, or change orientation during back travel, so as to preventpuncture of the local anatomy. A configuration as outlined in thisnon-limiting example may be advantageous for providing contact with thelocal anatomy without significant risk of damaging the adjacent anatomy(e.g. puncturing a vessel wall, etc) which may be a concern withstiffer, more traditional structures. Such microfingers may include acharacteristic width of less than 200 um, less than 100 um, less than 50um, less than 25 um, less than 10 um.

In aspects, one or more microfingers in accordance with the presentdisclosure may include a substantially hyper elastic material (e.g.formed from a memory alloy material, a superelastic material, a springsteel, etc.) so as to effectively deploy from a very small deploymenttube/catheter and expand outward to accommodate a large range of vesseldiameters. Such a configuration may be advantageous in so far as a smallnumber of unit sizes may be suitable for treating a wide range ofanatomical structures. In addition, the designed curvature and form of amicrofinger may be substantially chosen so as to further enable a widedeployable range of movement.

A surgical tool including a plurality of microfinger arrays (i.e.clusters of microfingers, fans of microfingers, etc.) may be employed soas to determine physiological response more remotely from an intendedsurgical site than may be available within a single array. Aspects ofthe disclosed concepts may be employed along the same lines by extendinginteractions between microfingers within an array, to inter-arrayinteractions. In aspects, a surgical tool including a plurality ofclustered microfinger arrays may be advantageous to analyze one or moreanatomical sites simultaneously from a plurality of sites(macroscopically separated sites). In one non-limiting example, twomicrofinger arrays may be arranged along a catheter based surgical tool,so as to interface with the walls of a lumen, at two or morelongitudinally separated distances. Physiological sensing from multiplemicrofingers may be advantageous for determining the extent ofneurological traffic between the plurality of sites, determine thedirection of traffic, determine if traffic from one direction or theother is blocked (i.e. after a surgical procedure, after RF currentapplication, after a denervation procedure, etc.). Such configurationsand methods for determining the state of a plurality of anatomical sitesis further disclosed throughout the text and appended figures of thisdisclosure.

In aspects, a system in accordance with the present disclosure may beused to monitor physiological activity associated with a surgical siteprior to, during and/or after a surgical procedure is applied thereto.Some suitable examples of surgical procedures include an RF ablation,Argon plasma coagulation, laser ablation, ultrasonic ablation,cryoablation, microwave ablation, abrasion, biopsy, delivery of asubstance (e.g. a chemical, a drug substance, an acid, a base, etc.),combinations thereof, and the like. The local physiological activity(e.g. nervous activity, blood perfusion, tonal changes, muscularsympathetic nerve activity, etc.) may be monitored with one more sensors(sensing tips, microfingers, etc.) and/or associated stimulators each inaccordance with the present disclosure. Additionally, alternatively, orin combination, a technique for assessing one or more physiologicproperties and/or states of an associated surgical site may be employed.Such techniques include assessing values and/or trends in bioimpedance,blood pressure, tissue oxygenation, tissue carbon dioxide levels, localtemperatures and changes thereof, and the like.

In aspects, the system may include a substrate onto which the sensingtips may be placed. Such a substrate may be formed from a balloon wall,a mesh, an interwoven ribbon array, a cloth, etc. The substrate mayinclude stretchable and/or flexible electronic materials.

Electrical interconnects may be formed from carbon nanotubes (e.g.SWNTs, MWNTs, etc.), nanowires, metallic wires, composites, conductiveinks, and the like.

In aspects, a portion, or all of the substrate and/or an associatedsubstrate carrier film may be formed from polyurethane, a silicone, ageneral elastomer, silk fibroin materials, or the like and/orcombinations thereof. Inclusion of microporous or fibrous substrates,may be advantageous to allow the substrate or substrate carrier film toadhere to the adjacent tissues via capillary effects (i.e. tendencies towick fluid from adjacent tissues into the substrate). The thickness offilms formed from the material may be less than 30 um thick, less than20 um, less than 10 um, less than 4 um, less than 1 um. Composites ofsomewhat stiffer materials (such as polyimide, PET, PEN, etc.) andsomewhat softer materials (e.g. silicones, polyurethanes, thermoplasticelastomers, etc.) maybe used to compromise between overall structuralstiffness and conformal capabilities of the substrate.

In aspects, patterned overcoats and/or composite layers may also be usedto expose electrode materials and/or sensing tips to the surroundingtissues in the vicinity of measurement regions, etc.

In one non-limiting example, the substrate may be at least partiallyformed from a silk material (e.g. Bombyx mori cocoons). The material maybe processed to remove sericin (which may cause undesirableimmunological response) using methods known in the art. The resultingmaterial can be solvent cast into shapes and crystallized to formself-supporting structures.

In aspects, adaptive temperature estimation may be used to bettercontrol the RF process. Such techniques may be supported by use of asurgical tool in accordance with the present disclosure, including oneor more sensing tips configured with temperature and/or bioimpedancemonitoring aspects. Modeling of changes in local bioimpedance may berelated to local temperature changes during the ablation process. Suchmeasurements as well as local thermoconductive properties, tissuethermoconduction, etc. may also influence the rates at which a localablation process may take place (i.e. as related to a thermal ablationprocess).

In aspects, a system in accordance with the present disclosure mayinclude one or more microsensors for monitoring nervous activity and/orrelated physiological activity during the RF ablation process. Someexamples of suitable monitoring techniques include electromyography(EMG), muscle sympathetic nerve activity (MSNA), mechanomyography (MMG),phonomyography (PMG), extracellular potentials, local field potentials,combinations thereof, and the like. Mechanomyography (MMG) measures theforce created by local muscle contractions caused by associated neuralactivity. Phonomyography (PMG) measures low frequency sounds associatedwith movement generated by associated neural activity. Traditionally,techniques such as MMG and PMG have been employed on externallyaccessible nervous and muscular tissues. One advantage of suchtechniques is that they may not be as easily affected by localelectrical noise as EMG and the effects of the nervous activity may begenerally sensed farther from the associated nerve than withelectromyographic techniques.

Alternatively, additionally or in combination the ascribed sensingtechniques may be combined with stimulation from local sources inaccordance with the present disclosure. Such stimulation and sensing maybe advantageous in determining functionality of local nerves without theneed to listen to complex biologically generated nervous activity.Furthermore, combined stimulation and sensing may be advantageous fordetermining functionality of a local nerve in real-time during adenervation and/or ablation procedure (e.g. the successive stimulationand sensing may be used to determine the degree of neurological blockand/or neuromuscular block there between). In aspects, suchfunctionality as well as directionality of the nerve signal propagation(e.g. efferent, afferent, etc.) may be more easily determined throughuse of combined local stimulation and sensing.

In aspects, one or more patterns of nerve stimulation may be used todetermine the function of the local nerve structures as well as one ormore aspects of neurological block and/or neuromuscular block that maybe caused by the surgical procedure (e.g. ablation), anesthesia,heating, chemical delivery, a related condition, etc.

In aspects, a single stimulation may be applied to elicit maximalresponse from the associated nerve at frequencies of less than 10 Hz,less than 1 Hz, less than 0.1 Hz. The downstream response as measured byany of the described techniques will depend on the frequency with whichthe stimuli are applied. In aspects, in order to allow for completerecovery of the nerve between stimulations, a frequency of less than orequal to 0.1 Hz may be advantageous.

During RF ablation of an associated nervous structure, the evokedelectrical and/or muscular responses may be dramatically affected. Suchchanges in the response may be useful in determining the state of thedenervation procedure. Thus they may be advantageous to determine theexact degree of RF energy that must be applied to a given structure inorder to cause sufficient denervation as desired by a surgicalprocedure. Such an approach may be advantageous to limit damage tosurrounding tissues caused by the denervation procedure, to ensuresuitable denervation has been achieved, to determine which nerves areaffected by the procedure, to control the extent of a denervationprocedure, etc.

Another technique for stimulation and sensing of the nervous responseincludes applying a rapid succession of pulses followed by a period ofinactivity. Pulse trains may be used to gradually force a nerve into ablocked state. The rate at which a nerve enters a blocked state andlater recovers therefrom may be a suitable indicator of the overallhealth and functionality of the nerve (i.e. a suitable metric fordetermining how a procedure has affected that nerve).

In aspects, the sensing of the nervous response may not need to be localto a surgical site, but rather downstream (in the sense of the flow ofan associated nervous signal) from the site. Such sensing of the nervousresponse may be advantageous for determining the progression of aparticular form of communication past a surgical site (i.e. afferent,efferent traffic, etc.).

In aspects, various mapping techniques may be applied to the surgicalsite, before, optionally during and after a surgical procedure. Somemapping techniques as used in cardiac interventions include pacemapping, activation mapping, entrainment mapping, and substrate mapping.It may be feasible to adapt such techniques for use in the intendedapplication. In general, these techniques may complement each other inlocalizing where amongst a surgical site to target the ablationprocedure.

In one non-limiting example, the micro fingers and/or associated sensingtips may be arranged in a polar configuration as an array of arches(i.e. an array of thin, arch-like elements each extending radiallyoutwards from a central axis). The arches may be attached at each end, afirst end connected to an axially oriented draw wire and the other endattached to a collar. The arches may be collapsed and/or expandedradially by extending and/or retracting the length of the draw wirebetween the first end and the collar respectively. The draw wire mayextend through the surgical tool to the operator or a machine, whereforce on the draw wire may be used to achieve this function. Thus thearches may be provided in a substantially collapsed state (i.e. withsmall overall diameter) for easy delivery to the surgical site. Upondelivery to the surgical site, the draw wire may be retracted, perhapsautomatically and/or with the help of an operator and the arches may beextended radially outwards, so as to contact the adjacent tissues of thevessel. Such a procedure may be used to bias the array of sensing tipsand/or micro fingers towards the walls of the vessel while maintainingblood flow there through.

Alternatively, additionally, or in combination the arches may bedeployed at a surgical site by removal of a restraining sheath (perhapsby retraction), by dissolution of a restraining element (e.g. anadhesive, an electrochemically destructible member, etc.), via thermalself-expansion of one or more elements of the arches, by combinationsthereof, or the like.

Additionally, or in combination to the aspects described herein, thesurgical system may be configured to monitor one or more physiologicparameters at one or more locations in the body remote from the surgicalsite. Some non-limiting examples of what may be monitored include waterconcentration, tone, blood oxygen saturation of local tissues, evokedpotential, electrolyte or solute concentration, stimulation/sensing ofnervous activity, electromyography, temperature, blood pressure,vasodilation, vessel wall stiffness, muscle sympathetic nerve activity(MSNA), central sympathetic drive (e.g. bursts per minute, bursts perheartbeat, etc.), tissue tone, blood flow (e.g. through an artery,through a renal artery), a blood flow differential signal (e.g. asignificantly abnormal and or sudden change in blood flow within astructure of the body, a vessel, an organ, etc.), blood perfusion (e.g.to an organ, an eye, etc.), a blood analyte level (e.g. a hormoneconcentration, norepinephrine, catecholamine, renin, angiotensin II, anion concentration, a water level, an oxygen level, etc.), nerve traffic(e.g. post ganglionic nerve traffic in the peroneal nerve, celiacganglion, superior mesenteric ganglion, aorticorenal ganglion, renalganglion, and/or related nervous system structures), combinationthereof, and the like.

In aspects, a surgical system in accordance with the present disclosuremay include one or more elements to monitor physiological activityand/or analyte levels (e.g. a hormone level), in and/or near to one ormore portions of a gland, an endocrine gland (e.g. an adrenal gland, anadrenal medulla, etc.), etc.

In another non-limiting example, a multi catheter surgical system may beemployed, each catheter in accordance with the present disclosure. Inthis non-limiting example, one or more first catheters may be used toprobe and/or ablate tissues at a first surgical site (e.g. an artery, arenal artery, a left renal artery, etc.) while one or more secondcatheters may be configured to monitor one or more physiologicparameters elsewhere in the body (e.g. in an alternative artery, a vein,in an organ, at a lymph node, at a ganglion, etc.), perhaps to determinethe effect of the surgical procedure there upon. In one non-limitingexample, the catheters may be inserted into the same or closelypositioned entry points into the body (e.g. the femoral artery, iliacartery, radial artery, femoral vein, etc.). Such a configuration may beadvantageous for providing a minimally invasive surgical tool to performthe surgical procedure (e.g. a sympathectomy, a renal sympathectomy,etc.).

FIGS. 1a-c show a surgical tool tip in accordance with the presentdisclosure in a delivery mode and a deployed mode. FIG. 1a shows adelivery catheter 110 with a micro surgical tool 120 held within (e.g.in a retracted position). The micro surgical tool 120 may include one ormore microfingers 125 in accordance with the present disclosure for usein a surgical procedure (e.g. a denervation procedure, a biopsy, anexcision procedure, etc.). The micro surgical tool 120 may be configuredso as to reversibly collapse down into the delivery catheter 110 uponretraction. The microsurgical tool 120 and/or delivery catheter 110 maybe connected 115 to a controller, a control unit (e.g. with a deploymentcontrol switch, etc.), an operator, a signal conditioning circuit, etc.

FIG. 1b shows a deployed micro surgical tool 120 with a plurality ofmicrofingers 125 a-c (i.e. in this case, 3 microfingers are shown). Inaspects, the microsurgical tool 120 may include any reasonable number ofmicrofingers 125 a-c. Each microfinger 125 a-c may be generally spacedapart from the others such that if the array is biased towards a tissuesite, they may form a pattern (e.g. a dotted line, a diamond, a ring,etc.). The microfingers 125 a-c may be expand outward (e.g. radially,axially, circumferentially, and/or combinations thereof) in one or moredirections when deployed from the associated delivery catheter 120. Thusthe microfingers 125 a-c may suitably engage with a local tissue site beit to monitor the site, ablate the site, a combination thereof, or thelike. One or more of the microfingers 125 a-c may include one or moresensing tips 130 a-d each in accordance with the present disclosure. Asshown in this non-limiting example, each microfinger 125 a-c includes asensing tip 130 a-c located, primarily at the end of the microfinger 125a-c. In addition, one microfinger 125 c includes another sensing tip 130d (e.g. perhaps a temperature sensor, a reference electrode, a flowsensor, etc.) located near to the end of the microfinger 125 c. Inaspects, a temperature sensor 130 d in the flow may be advantageous toevaluate local flow changes (turbulence, micro heating, etc.) that mayoccur during an associated surgical process.

FIG. 1c shows a deployed microtool 135 from a delivery catheter 111,after being placed within a lumen within a body (i.e. a vessel, anartery, a vein, a tubule, etc.). The microtool 135 includes a pluralityof microfingers 140 a-f each arranged radially around the axis of thelumen and biased against the wall of the lumen 11. In this non-limitingexample, the microfingers 140 a-f are shown with electrode based sensingtips 141 a-f. The microfingers 140 a-f are also shown with curled tips,configured so as to minimize stresses applied to the lumen wall 11during deployment. The electrode based sensing tips 141 a-f may includeone or more exposed electrically conducting regions (i.e. a metallicmaterial, a conducting polymer, a conjugated polymer, a carbon material,combinations thereof, or the like) so as to interface electrically withthe adjacent lumen wall 11. In aspects, the microfingers 140 a-f may becoated with an insulating layer in accordance with the presentdisclosure, so as to minimize fluid contact there along during amonitoring, stimulation, and/or ablation process applied therewith.

FIGS. 2a-b show deployed surgical microtools in accordance with thepresent disclosure interacting with a local surgical site. FIG. 2a showsa cross section of a vessel located at a surgical site. The vesselincludes a vessel wall 12, which may have one or more anatomicalfeatures that are to be operated upon (i.e. nerves, tumor, plaque,etc.). An array of microfingers 210 in accordance with the presentdisclosure is shown interacting with the vessel wall 12. For purposes ofdiscussion, an associated delivery catheter 215 is also shown in withinthe vessel wall 12. In the example shown, the microfinger array 210 maybe swept along the vessel wall by counter clockwise rotation 212 aboutthe delivery catheter 215 (or clockwise, depending on the preference ofthe operator, design of the catheter, etc.). Such motion may be providedby an operator (e.g. by torsion of the micro surgical tool shaft), by amechanism within the tool, by a flexural structure of the microfingerarray 210 (e.g. a helical structure so as to prefer rotational sweepingof the anatomy as the array is pulled through the vessel), combinationsthereof or the like. The microfingers of the array 210 may include oneor more sensing tips each in accordance with the present disclosureconfigured to interact with the lumen wall 12. In one aspect, shown, oneor more of the sensing tips may be configured to pass a current 214locally between one or more of the sensing tips. Such current may beused to stimulate the local anatomy (i.e. as part of astimulation/response monitoring system), or at higher intensities, as anRF source for ablation of local tissues (i.e. to perform a localizedsympathectomy, etc.). In aspects, the microfinger array 210 may beconfigured to provide a combination of sensing and ablation (i.e. toperform a controlled sympathectomy procedure, to vary the degreetransmission of local signals, to affect one or more local anatomicalsites, one or more receptors, etc.).

FIG. 2b shows a multi-array micro surgical tool including two arrays ofmicrofingers 220 a-b simultaneously interacting with substantiallyopposite sides of the vessel wall 13. One microfinger array 220 b isshown ablating a local tissue site, thus forming an ablation zone 222. Ahypothetical RF ablation current pathway 224 is shown in the figure forpurposes of discussion. The multi-array microsurgical tool may berotated about the delivery catheter 225, in this example, in a counterclockwise direction 230 with respect to the viewer. The microfingers 220a-b include one or more sensing tips 226, in this case, the sensing tip226 near the ablation site is configured to deliver current to and/oraccept current from the local tissues. In a usage scenario, the sensingtips 226, may be configured to monitor local electrophysiologicalactivity in the lumen wall while the surgical tool is rotated about thedelivery catheter 225, when an anatomical site 235 of interest (i.e. anerve plexus, a high traffic nerve plexus, a tumor, etc.) is detected,the ablation process may be initiated through select microfingers in thearrays 220 a-b. Current and/or sensing potentials may be providedbetween a first and one or more sensing tips 226 in the arrays 220 a-b,or between a sensing tip 226 and an external electrode (not explicitlyshown), located in a direction 237 away from the lumen wall 13.

FIG. 2c shows a radially expanding micro surgical tool including anarray of microfingers 250 a-f (not all elements numbered due toclutter), each microfinger configured to bias against the lumen wall 14upon deployment from the delivery catheter 255. The microfingers 250 a-fmay include one or more sensing tips 260 (not all numbered due toclutter) each in accordance with the present disclosure, configured tosimultaneously interact with localized regions of the vessel wall 14upon deployment. A collection of microfingers 250 a-c is shown in theprocess of ablating a local tissue site, thus forming an ablation zone265. A hypothetical RF ablation current pathway 267 is shown in thefigure for purposes of discussion. In a usage scenario, the microfingers250 a-e and associated sensing tips 260 may be configured to biasagainst the lumen wall 14 and to monitor local electrophysiologicalactivity in the lumen wall while the surgical tool is positionedtherein, and/or drawn along the axis of the lumen during a mappingprocess, etc. In the given example, an anatomical site 269 of interest(i.e. a nerve plexus, a high traffic nerve plexus, a tumor, etc.) isdetected near to sensing tip 260, and an ablation process may beinitiated through select microfingers in the arrays 250 a-c. In aspects,the anatomy of interest may be mapped, and/or the layout of the anatomydetermined either via movement of the microtool along the length of thelumen, via coordinated sensing, and/or stimulation/sensing betweenrelated microfinger arrays (not explicitly shown), etc. via one or moremethods in accordance with the present disclosure. In aspects, two ormore of the microfingers 250 d-e may be configured to pass current 272there between, to measure an electrophysiological signal there between,etc. In aspects, the system may include and/or be coupled to acontroller, the controller configured to analyze the signals obtainedfrom each microfinger and determine the location and/or state of ananatomical site of interest, determine the extent of an ablationprocedure, etc.

FIG. 3 shows a plurality of micro-tips monitoring physiological responseand/or stimulating local tissue during a surgical procedure. Threesensing tips 310 a-c are shown abutted against a vessel wall 15. Thesensing tips 310 a-c may be attached to microfingers, substrates,balloons, or the like (each in accordance with the present disclosure).

In a first example 320, the first sensing tip 310 a is used both tostimulate the local tissues (e.g. in order to determine proximity to alocal nerve, to determine one or more aspects of local nerve function,etc.), and to ablate the local tissues (e.g. as part of a denervationevent, to destroy cancerous tissue, to cauterize a tissue site, etc.).The second sensing tip 310 b is configured to monitor local temperaturevariation of the tissues with which it may be in contact during asurgical procedure. The third sensing tip 310 c is configured to sensean electrical response from the local tissues during a surgicalprocedure (e.g. evoked potential, EMG, microvoltage, current flow,etc.).

FIG. 3 also shows a time series of events for the first example 320,shown during an RF ablation procedure. During a testing period 316 oneor more stimulatory pulses 321 may be applied to the first sensing tip310 a and monitored 322 by one or more of the other tips (in this casethe third sensing tip 310 c). Perhaps during this period the combinationof stimulation and response satisfies a predetermined surgical criterionfor initiating local ablation (i.e. local nerves identified, overactiveneurological traffic detected, etc.). During the ablation period 317, anRF signal 323 is applied to the tissues via the first sensing tip 310 a(e.g. perhaps with current flow to the third sensing tip 310 c, to aremote macroelectrode, combinations thereof, etc.). The RF ablation maybe performed sequentially or with a duty cycle so as to evaluate theprogress throughout. It may also be performed in one sequence. The RFsignal as measured by the third sensing tip 310 c may be used to assistwith determining bioimpedance of the local tissues, the state of thelocal tissues, etc. during the ablation process. In this non-limitingexample, local tissue temperature 325 near to the ablation site (asmonitored via the second sensing tip 310 b) may also be used to estimatethe extent of the ablation process, perhaps in combination with sensingvia the third sensing tip 310 c, and/or bioimpedance measurements. Whenthe temperature and/or ablation process reaches a setpoint, the ablationis stopped and the local tissues are allowed to recover. This timeframeis shown as a recovery period 318. In aspects, the recovery period 318may be less than 2 min, 1 min, 30 s, 10 s, 1 s, 0.1 s. In an additionaltesting period 319, the first sensing tip 310 a may stimulate the localtissues and the third sensing tip 310 c may monitor for a response. Inthis case, an absent response indicates that the ablation procedure hasproceeded sufficiently for the intended purposes and the microsurgicalsensory tip array may be advanced to a new site or removed from thelumen.

FIG. 3 also shows a time series of events for a second example 330,shown during an RF ablation procedure. In this example, the firstsensing tip 310 a and the third sensing tip 310 c are configured so asto monitor local electrophysiological response of the tissues (i.e. tomonitor extracellular neurological activity, local field potentials,electromyographic signals, etc.) and the second sensing tip 310 b isconfigured to apply an RF current to the lumen wall 15 adjacent thereto. During a testing period 331 electrophysiological responses aremonitored at the first sensing tip 310 a and the third sensing tip 310c. As can be seen from the a-site response curve 335 and the c-siteresponse curve 337, prior to an ablation, the coherence between thesensed signals is high (i.e. closer to 1 than to 0). During the ablationperiod 332 an RF signal 336 is applied to the tissues via the secondsensing tip 310 b (e.g. perhaps with current flow to the first sensingtip 310 a, the third sensing tip 310 c, or to a remote macroelectrode,combinations thereof, etc.). The RF ablation may be performedsequentially or with a duty cycle so as to evaluate the progressthroughout. It may also be performed in one sequence. The associated RFsignal as measured by the first sensing tip 310 a and the third sensingtip 310 c may be used to assist with determining bioimpedance of thelocal tissues, direction of RF current flow from the second sensing tip310 b, the state of the local tissues, etc. during the ablation process.When the temperature and/or ablation process reaches a setpoint, theablation is stopped and the local tissues are allowed to recover. Thistimeframe is shown as a recovery period 333. In aspects, the recoveryperiod 333 may be less than 10 min, less than 5 min, less than 2 min,less than 1 min, less than 30 s, less than 10 s, less than 1 s, lessthan 0.1 s, or the like. During the recovery period electrophysiologicalresponses are monitored at the first sensing tip 310 a and the thirdsensing tip 330 c. As can be seen from the a-site response curve 335 andthe c-site response curve 337, after the ablation procedure 332, thecoherence between the sensed signals has changed dramatically (i.e. ithas decreased significantly). The measure of coherence between thesignals before and after a surgical procedure, may be a quantifiableindicator of a state of completion thereof, it may be a quantifiablemeasurement of the local percentage change in neurological activity, itmay be an indicator of the ratio of afferent/efferent traffic in thevicinity of the sensing tips 310 a-c, and the like. In this case, amarkedly changed coherence between the a-site signal 335 and c-sitesignal 337 indicates that the ablation procedure has proceededsufficiently for the intended purposes and the microsurgical tool inaccordance with the present disclosure, may advance to a new site orremoved from the lumen. Such coherence based determination of proceduraloutcomes may be a suitable method for automatically performingassociated surgical procedures, for controlling the extent of suchsurgical procedures, and the like.

FIGS. 4a-b show interactions between multiple micro-tips and the localvasculature in accordance with the present disclosure. FIG. 4a shows amicro surgical tool in accordance with the present disclosure includingthree arrays of microfingers 410 a-c interacting with the vessel walls16 of a local anatomical site. The microfinger arrays 410 a-c are shownin a deployed state from a delivery catheter 415 in accordance with thepresent disclosure. In aspects, the microfinger arrays 410 a-c may bearranged so as to sufficiently cover the lumen walls 16 afterdeployment. In aspects, the microfinger arrays 410 a-c may be sweptalong the vessel walls via torsional action of the micro surgical toolor aspect thereof. The microfinger arrays 410 a-c are shown as swept ina counter clockwise direction 420 in the FIG. 4a . A local contact sitebetween a microfinger array 410 c and the vessel wall 16 is shown inmore detail in blowup B. One or more of the microfingers may include oneor more sensing tips in accordance with the present disclosure. FIG. 4bshows a magnified view of blowup B. Three micro-tips 430 a-c included inthe microfinger array 410 c are shown pressed against a local tissuesite of the lumen wall 16. Each microtip includes a sensing tip 435 a-cin accordance with the present disclosure. In this case, the sensingtips shown may be electrodes, MMG sensing elements, force sensingelements, temperature sensors, any sensing tip in accordance with thepresent disclosure, combinations thereof, or the like. A singlemicro-tip 430 b is shown with a full outline for further discussion.During a procedure, the micro-tip 430 b may be swept, oscillated, etc.the tip will interact locally with the tissue (e.g. via transversemovement, changing contact forces, etc.). Such movement may be directedtowards/away from the tissue surface (i.e. in a direction normal 445 tothe tissue surface), and/or along the surface of the tissue (i.e. in adirection parallel 440 to the tissue surface). Equipped with anassociated deflection sensing tip and/or an interfacial pressure sensingtip, these movements may be used to elucidate local physiologicproperties (e.g. mechanical compliance, tone, etc.) of the tissues.Alternatively, additionally, or in combination a suitably equippedmicro-tip 430 b may be used to measure local mechanomyographic response,perhaps due to electrophysiological activity in the vicinity of, orupstream from the tip 430 b. Such information may be used for severalintended purposes as detailed throughout this disclosure.

In aspects, the microfinger may be equipped with a needle electrode tip(perhaps formed as a structural extension of the flexure, etc.). Theneedle electrode tip may be configured such that upon applied torsion ina given direction, the needle may pierce the local tissues so as toenhance the electrical interface between the microfinger and thetissues. Such a needle electrode tip may be integrated into one or moremicrofingers and/or sensing tips in accordance with the presentdisclosure.

FIGS. 5a-c show some non-limiting aspects of micro-tips and/or tips ofone or more microfingers in accordance with the present disclosure. FIG.5a shows schematic diagrams for the cross sections of four non-limitingexamples of micro-tips in accordance with the present disclosure (i.e.in this case including one or more exposed electrode sensing tips). FIG.5a shows a schematic of the tip of a micro-finger 510 including a coreflexure 512 (e.g. a superelastic spring-like material, optionallyelectrically conducting, a wire, a flex circuit, a micro interconnect,etc.), with an isolating layer 514 (e.g. an oxide, a dielectric coating,a radio-opaque coating, etc.) applied selectively to regions thereof. Atthe tip of the micro-finger 510, a region 516 of uncoated core flexureis exposed. This region 516 may, provide an electrode property forinteracting with local tissues, provide a site for attachment of amicrosensor, etc. In aspects, the exposed region 516 may be coated withone or more electrode materials (i.e. one or more metals, alloys,conducting polymers, composites, carbon materials, conjugated polymers,combinations thereof, or the like). In the example shown, the exposedregion 516 is oriented to one side of the neutral axis of the coreflexure 512. Such orientation may be advantageous for maintainingcontact with an adjacent tissue surface while sweeping or moving themicro-tip 510, while biasing the micro-tip 510 against a tissue surface,etc. In aspects, the micro-tip 510 may be configured with a curvature,oriented so as to ensure the exposed region 516 will face an approachingtissue surface during deployment.

FIG. 5a shows a schematic of a micro-tip 520 in accordance with thepresent disclosure. The micro-tip 520 is shown with a core flexure 522and an insulating layer 524, each in accordance with the presentdisclosure. The micro-tip 520 may include an axially oriented exposedregion 526, located at the tip thereof. The axially oriented exposedregion 526 may be configured for electrically interfacing with anadjacent tissue, with a sensing tip (i.e. a sensing tip in accordancewith the present disclosure), or the like. Such a configuration may beadvantageous for the simplicity of manufacture, etc. The core flexure522 may be shaped in the vicinity of the exposed region 526 so as toefficiently interface against an adjacent tissue surface.

FIG. 5a further shows a schematic of a microfinger 530 in accordancewith the present disclosure. The microfinger 530 may include acore-flexure 532 and an insulating layer 534 each in accordance with thepresent disclosure. The microfinger 530 may include an exposed region536 in accordance with the present disclosure. The core-flexure 532 maybe shaped to a point and/or an edge within the vicinity of the exposedregion 536. Such a configuration may be advantageous to cause themicrofinger 530 to grip and/or penetrate into a tissue surface whenbrought into contact therewith.

FIG. 5a shows a schematic of a micro-tip 540 in accordance with thepresent disclosure. The micro-tip includes a plurality of core flexures542 a-b, each in accordance with the present disclosure and one or moreregions covered with an insulating layer 544 in accordance with thepresent disclosure. In the example shown, the micro-tip 540 may includea plurality of exposed regions 546 a-b oriented along the length or nearthe tip thereof. The exposed regions 546 a-b may act as electrode basedsensing tips in accordance with the present disclosure, may beconfigured so as to accept one or more sensing tips in accordance withthe present disclosure. Such a configuration may advantageous formonitoring local electrophysiological signals, bioimpedance, impedancebetween the tip region 546 b and the shank region 546 a (i.e. so as todetermine if the tip is in contact with an adjacent fluid, etc.).

In aspects, the core flexures 542 a-b may include a flex circuit with aplurality of interconnects. The exposed regions 546 a-b may include aplurality of contacts for interfacing between the core flexures 542 a-band one or more sensing tips attached thereto.

In aspects, one or more of the microfingers 510, 520, 530, 540 mayinclude one or more electrical interconnects arranged along the lengththereof, one or more distributed integrated circuit elements, etc.

In aspects, the microtip 510, 520, 530, 540 may include a platedelectrode structure, a mushroom like electrode (e.g. so as to increasethe contact surface area between the microtip and the tissues), a benttip, a loop formation, a foot-like electrode element, etc.

In aspects, the microtip 510, 520, 530, 540 may be equipped with aneedle electrode tip (perhaps formed as a structural extension of theflexure, etc.). The needle electrode tip may be configured such thatupon applied torsion in a given direction, the needle may pierce thelocal tissues so as to enhance the electrical interface between themicrotip and the tissues.

FIG. 5b shows a ribbon like microfinger 550 in accordance with thepresent disclosure. The ribbon microfinger 550 may include a substrate552 in accordance with the present disclosure, a spring-like material, aflexible polymeric material, or any combination thereof. As shown, theribbon microfinger 550 includes electrical interconnects 554 coupled tothe substrate 552 for communicating one or more electrical signals alongthe length thereof as well as regions 556 a-b at the tip suitable forinteracting with local tissues (i.e. a site suitable for a sensing tipin accordance with the present disclosure). The electrical interconnects554 may be coupled to one or more of the regions 556 a-b (i.e. coupledwith one or more electrode based sensing tips, coupled to one or moresensing tip interconnects, etc.).

FIG. 5c shows a helical ribbon microfinger 560 in accordance with thepresent disclosure. The helical ribbon microfinger 560 may include aplurality of sensing tips 566, each coupled to a substrate 562 andoptionally to one or more interconnects 566 each in accordance with thepresent disclosure. The substrate 562 may include one or more embeddedmicrocircuits 568, coupled to the sensing tips 566 and/or theinterconnects 566, so as to provide a signal conditioning function,switching function, multiplexing functionality, or the like, inaccordance with the present disclosure.

A ribbon microfinger 550, 560 may be configured so as to take on aparticular shape (i.e. a hook like shape 559 as shown in FIG. 5b , ahelical shape 569 as shown in FIG. 5c , or the like) upon deployment,perhaps from a delivery catheter in accordance with the presentdisclosure.

Such a ribbon microfinger 550, 560 may be attachable to a micro ballooncatheter, wound around a stent-like mesh, etc. so as to provide supportthereto and/or to bias the ribbon microfinger into the adjacent tissuesfor purposes of monitoring, stimulating, and/or performing a procedure(i.e. heating, ablating, abrading, etc.).

In aspects, the ribbon microfinger 550, 560 may include one or morecircuit elements 568 (e.g. a switch, an amplifier, etc.) in order tocontrol direction of, perform a conditioning function to, alter theimpedance of, etc. a signal passed along the microfinger (i.e. to orfrom the micro-tip).

FIGS. 6a-b show a microfinger 610 in accordance with the presentdisclosure. FIG. 6a shows an axial view of a microfinger 610demonstrating an optional multi-axial curvature thereof, as well as asweeping action 620 that may be achieved therewith during a procedurewith the microfinger 610 biased against a lumen wall 17. FIG. 6b shows alongitudinal view of the same microfinger 610, demonstrating additionalcurvature thereof as well as contact between the microfinger 610 andcoupled sensing tip 630 with a local anatomical surface (i.e. in thiscase a vessel wall 17). An arrow 620 is shown in FIGS. 6a-b todemonstrate the sense of rotation of the microfinger 610 as it is sweptover a vessel wall 17. A lumen axis 18 is also shown so as todemonstrate the approach for the microfinger 610 after deployment from adelivery catheter (not explicitly shown).

FIGS. 7a-b show a micro-tip 710 including a MMG sensing element and aresponse in accordance with the present disclosure. The micro-tip 710includes an interfacial force sensing element 720 (e.g. a nanomaterialcoating, a piezoresistive coating, a piezoelectric coating, etc.) and aflexural sensing element 730 (e.g. a nanomaterial coating, apiezoresistive coating, a piezoelectric coating, etc.). Both elements720, 730 may be coupled to the substrate 715 of the microtip 710. Themicro-tip 710 maybe subsequently connected 740 to a controller ormicrocircuit (not explicitly shown) via one or more interconnects,included in the micro-tip (i.e. along a substrate 715 and/or coreflexure thereof). Such electrical elements may be embedded into thesubstrate 715, into a delivery catheter (not explicitly shown), coupledto one or more elements of an associated surgical tool, or the like. Theinterfacial force sensing element 720 may be configured to measure acontact force between the microfinger 710 and an adjacent tissuesurface. The flexural sensing element 730 may be configured to measureflexure of the micro-tip 710 during such interaction. Thus, viamonitoring signals from both sensing elements 720, 730 a localcompliance of the adjacent tissues may be measured/inferred (i.e. viameasurement of contact force, flexure, and/or some combination thereof).

FIG. 7b shows a time series of conditioned signals received from aflexural sensor and an associated interfacial force sensor during astimulation event 750 (e.g. perhaps as excited by another sensing tipincluded in an associated micro surgical tool, etc.). The stimulationand associated response from each sensor 720, 730 is shown on the timeseries (i.e. force sensing 760 and strain sensing 770 respectively). Inaspects, the stimulation may be caused by an electrical stimulationevent, perhaps elsewhere in the body, in a related neurological circuit,or the like. The combination of force sensing 760 and strain sensing 770signals may be combined to form an MMG signal. The resulting MMGsignal(s) may be sufficiently free from electrical noise that may bepresent when measuring via alternative measures.

FIGS. 8a-b show a schematic of a micro-tip 810 in accordance with thepresent disclosure. FIG. 8a shows a micro-tip 810 with an integratedtemperature sensing tip 840. The temperature sensing tip 840 may includea bimetallic configuration, a silicon sensing element, an infraredsensing microcircuit, etc. The micro-tip 810 includes a plurality ofelectrical interconnects directed between the temperature sensing tip840 and a controller 850 (e.g. a local control circuit, an analog todigital converter, a local signal amplifier, etc.). The micro-tip 810may include a substrate and/or core flexure 820 along which suchelectrical interconnects may be coupled. The micro-tip 810 may includeone or more insulating layers 830 in accordance with the presentdisclosure.

FIG. 8b shows a time series measurement from the temperature sensing tip840 during a series of local RF ablation pulses 860. Local temperaturerise 870 as measured by the temperature sensing tip 840 may be used tocontrol the overall pulse width of each RF pulse, the overall RF energydelivery, the RF power, etc. In aspects, such information may be coupledwith one or more signals obtained from an associated sensing tip inaccordance with the present disclosure. Such information may becollectively used to determine the extent of an ablation process, indeciding to continue with an ablation procedure, or the like.

FIG. 9 shows a micro surgical tool 910 deployed at a surgical site 19,20, 21 in accordance with the present disclosure. The micro surgicaltool 910 includes a delivery catheter 915 and a plurality of microfingerarrays 920 a-b, the microfinger arrays 920 a-b penetrating into therenal artery 21 of a subject. The micro surgical tool 910 includes aguide wire 940 (alternatively a guiding arm, a control arm, etc.)coupled to the microfinger arrays 920 a-b such that they may becontrolled by an external operator, robot, etc. (i.e. coupled 950 to themicro surgical tool 910). In the arrangement shown, one of themicrofinger arrays 920 b is attached to a local signal conditioningintegrate circuit 930, positioned so as to provide conditioning ofsignals sensed at the microfinger tips 920 b, perhaps to convert thesignals into digital forms, to provide a low impedance source, etc. Theother microfinger array 920 a is oriented adjacent to an anatomical site20 of interest (i.e. in this case nerve plexus). The presence/locationof the anatomical site 20 of interest may have been determined viamonitoring of one or more sensing tips within the microfinger arrays 920a-b during a sweeping procedure, etc. Having identified/located theanatomical site 20 of interest, the operator, controller, etc. 950 mayperform a surgical procedure thereupon.

FIGS. 10a-d show non-limiting examples of monitoring methods inaccordance with the present disclosure.

FIG. 10a shows a lumen (i.e. a vessel, a vein, an artery, a renalartery, etc.) prior to a surgical process. Two sensing sites are shown,distal 1015 and proximal 1010 to the intended surgical site. An ablationcatheter tip 1020 (e.g. although shown as a separate unit, it may beincluded in an associated microfinger array as a sensing tip inaccordance with the present disclosure) including an ablation electrode1025 is placed in contact with the tissues between the sensing sites.One or more sensing tips may be placed at the sensing sites 1010, 1015,among others, as well as optionally at the surgical site (i.e. toperform a combination of sensing and procedures). Prior to initiation ofthe surgical procedure, nervous activity may be detected at both sensingsites 1010, 1015. In aspects, the correlation between theelectrophysiological signals (i.e. neurological signals,electromyographic signals, mechanical myographic signals, etc.) may berelatively high prior to initiation of a surgical procedure. In aspects,the correlation between the electrophysiological signals may include thestep of extracting a portion of each signal that is substantially commonto both signals for analysis.

FIG. 10b shows a lumen (i.e. a renal artery) after a surgical ablationprocess. Two sensing sites are shown, distal 1040 and proximal 1035 tothe surgical site. An ablation catheter tip 1020 (e.g. although shown asa separate unit, it may be included in an associated microfinger arrayas a sensing tip in accordance with the present disclosure) equippedwith an ablation electrode 1025 is placed in contact with the tissuesbetween the sensing sites. The ablation catheter tip 1020 has beenemployed as part of a surgical procedure to form an ablation zone 1030,in this case shown substantially around the circumference of thearterial wall around the surgical site forming the ablation zone 1030.After completion of the ablation procedure, nervous activity may nolonger be detected at one or more of the sensing sites 1035. In thisexample, the ablation procedure has substantially blocked afferent nervetraffic from proceeding through the ablation zone 1030. In aspects,efferent nerve traffic may still be detectable at the proximal sensingsite 1035, and afferent nerve traffic may still be detectable at thedistal sensing site 1040. The correlation between the resulting signalsmay be used to quantify the state of the ablation process, the extent ofdenervation, etc.

In aspects, the above method and variations thereof may be used toextract the afferent from the efferent nerve traffic in the vicinity ofa surgical site of interest. In aspects, the surgical procedure mayinclude the application of energy to the surgical site in asubstantially low dosage so as to temporarily inhibit function of theneurological anatomy in the vicinity thereof. In one non-limitingexample, the energy may be used to heat the local tissues to atemperature of greater than 40 C, 45 C, 50 C so as to form the temporaryblock. Signals obtained by the distal and proximal sensing sites 1035,1040 may be used to determine when the block has occurred, how the blockhas affected the traffic, and to distinguish, post block, informationabout the efferent and afferent nerve traffic in the vicinity of thesurgical site.

In aspects, following a temporary block, if the procedure has favorablyaltered the neurological traffic, a more durable procedure may becompleted (i.e. an ablation procedure, a chemical denervation, a thermalablation process, a radiation based ablation, etc.). Such an approachmay be advantageous for safely determining the ideal targets for asurgical procedure, for minimizing damage to the surrounding tissues incompleting a denervation procedure, and the like.

FIG. 10c shows a lumen (i.e. a renal artery) prior to a surgicalprocess. Two sensing sites are shown, distal 1050 and proximal 1045 tothe intended surgical site and a pacing site 1055 is shown located toone side of the intended surgical site. An ablation catheter tip 1020(e.g. although shown as a separate unit, it may be included in anassociated microfinger array as a sensing tip in accordance with thepresent disclosure) is placed in contact with the tissues between thesensing sites. One or more sensing tips may be placed at the sensingsites 1045, 1050, among others, as well as optionally at the surgicalsite (i.e. to perform a combination of sensing and procedures). Prior toinitiation of the surgical procedure, both a pacing signal 1055 as wellas associated nervous activity may be reliably detected at both sensingsites 1045, 1050. The pacing signal 1055 may be used to determine atransmission velocity along the associated anatomy between the pacingsite 1055 and each of the sensing sites 1045, 1050, may be used todetermine the transmission characteristics of the anatomy between sites,etc. In aspects, the coherence between the electrophysiological signals(i.e. neurological signals, electromyographic signals, mechanicalmyographic signals, etc.) may be relatively high prior to initiation ofa surgical procedure. In aspects, the coherence in combination with thepacing signal may be advantageous in extracting the relevant informationto make an assessment of neurological function quickly and reliably,even in the presence in considerable background noise, movement, andphysiologically relevant neurological activity.

In aspects, the step of evaluating the coherence between theelectrophysiological signals may include the step of extracting aportion of each signal that is substantially common to both signals foranalysis.

FIG. 10d shows a renal artery after a surgical ablation process. Twosensing sites are shown, distal 1065 and proximal 1060 to the surgicalsite and a pacing site 1070 is shown located to one side of the intendedsurgical site. An ablation catheter tip 1020 (e.g. although shown as aseparate unit, it may be included in an associated microfinger array asa sensing tip in accordance with the present disclosure) with anablation electrode 1025 is placed in contact with the tissues betweenthe sensing sites 1060, 1070. The ablation catheter tip 1020 has beenswept around the circumference of the arterial wall around the intendedsurgical site forming an ablation zone 1030. After completion of theablation procedure, nervous activity may no longer be detected at one ormore of the sensing sites 1060, 1065 even under the continued action ofthe pacing signal 1070.

In aspects, one or more of the distal sensing 1015, 1040, 1050, 1065,proximal sensing 1010, 1035, 1045, 1060, pacing 1055, 1070, and surgicalprocedure (i.e. formation of a blocked region, an ablation zone 1030,etc.) may be completed by one or more sensing tips each in accordancewith the present disclosure.

FIGS. 11a-g show some non-limiting examples of ablation patterns appliedto a renal artery in accordance with the present disclosure.

FIG. 11a shows a lumen 1105 (i.e. a tubule, a vessel, an artery, a vein,a renal artery, etc.) prior to the application of a surgical procedurethereto. As outlined in the Figure, a range of neurological structures(i.e. nerve plexuses) 1110, 1115, 1120, are visible within the wall andsurrounding adventitia of the lumen 1105. In aspects, the lumen 1105 mayprovide a conduit for flow of a fluid (i.e. blood, bile, lymph, urine,feces, etc.), and to interconnect one or more organs, and or aspects ofan organ (i.e. an intra-organ vessel).

FIG. 11b shows the lumen (i.e. the renal artery) with acircumferentially ablated region 1125 generated by a micro surgical toolin accordance with the present disclosure. Sensing tips located toeither side or within the ablation zone 1125 may be used to confirmeffective ablation, control the ablation process itself, for decisionmaking related to the size and placement of the ablation site, to limitthe overall amount of damage caused by the ablation procedure, or thelike. In this non-limiting example, the associated ablation zone 1125may be produced by collective activation of a plurality of sensing tips,arranged around the circumference of the lumen 1105, by swept motion ofone or more sensing tips during a procedure, or the like.

FIG. 11c shows the lumen (i.e. the renal artery) after a selectivelytargeted nerve bundle 1127 has been ablated by a micro surgical tool inaccordance with the present disclosure. Sensing tips included in themicro surgical tool may have been used to locate target tissues forablation, monitor the ablation process itself, to avoid ablation ofnerve bundles that are not to be surgically treated, to confirmeffective ablation, and to limit the overall amount of damage caused bythe ablation procedure. In this non-limiting example, the nerve bundle1127 is ablated at local sites 1130 along the length thereof so as tolimit damage to the surrounding tissues. In aspects, such ablationprofiles may be formed during collective activation of a plurality ofsensing tips each in accordance with the present disclosure, viaselective ablation of tips during a longitudinal sweeping process, viaselective ablation of tips during a tracking process, combinationsthereof, or the like.

FIG. 11d shows the lumen (i.e. renal artery) after a group ofselectively targeted nerve bundles 1132, 1134 have been ablated by amicro surgical tool in accordance with the present disclosure. Inaspects, sensing tips included in the micro surgical tool may have beenused to locate target tissues for ablation, monitor the ablation processitself, to avoid ablation of nerve bundles that are not to be surgicallytreated, to confirm effective ablation, and to limit the overall amountof damage caused by the ablation procedure. In this non-limitingexample, the nerve bundles 1132, 1134 are ablated at local sites 1135along the length thereof so as to limit damage to the surroundingtissues. Local sites 1135 may be placed so as to minimize potentialdamage to nearby anatomical features, which may not be intended targetsfor the surgical procedure.

FIG. 11e shows the lumen (i.e. renal artery) after a selectivelytargeted nerve bundle 1142 has been ablated by a micro surgical tool inaccordance with the present disclosure. In aspects, sensing tipsincluded in the micro surgical tool may have been used to track thetargeted tissues as the ablation process is occurring (so as toestablish an ablation path along the target tissues), locate targettissues for ablation, monitor the ablation process itself, to avoidablation of nerve bundles that are not to be surgically treated, toconfirm effective ablation, and to limit the overall amount of damagecaused by the ablation procedure. In this non-limiting example, thenerve bundle 1142 is ablated along a continuous strip 1140 as followedwith guidance from the sensing tips. Such a long stretch of ablatedtissue may be employed to limit the potential for regeneration after thesurgical procedure has been completed. In aspects, feedback from signalsobtained from one or more sensing tips may be used to guide the surgicalhardware during the surgical procedure (i.e. ablation, chemicalsubstance delivery, etc.).

FIG. 11f shows the lumen (i.e. renal artery) after selectively targetednerve bundles 1152, 1154, 1156 have been ablated by a micro surgicaltool in accordance with the present disclosure. In aspects, the sensingtips included in the micro surgical tool may have been used to locatetarget tissues for ablation, to identify tissues for ablation, monitorthe ablation process itself, to avoid ablation of nerve bundles that arenot to be surgically treated, to confirm effective ablation, and tolimit the overall amount of damage caused by the ablation procedure. Asubstantially helical tool path 1150 is shown, as the micro surgicaltool traced around the walls of the renal artery during the ablationprocedure. In this non-limiting example, the nerve bundles 1152, 1154,1156 are ablated at a plurality of local sites 1145 along the lengththereof so as to limit damage to the surrounding tissues. In aspects,the targeted neuroanatomical structures 1152, 1154, 1156 may be treatedalong the length thereof in order to control the post-surgical regrowthrate, or the like.

FIG. 11g shows a lumen 1160 (i.e. a vessel, an artery, a renal artery, avein, a tubule, etc.) after a selectively targeted treatment zones 1175,1180, 1185 have been formed around target anatomical structures 1165,1167, 1169 by a micro surgical tool in accordance with the presentdisclosure. Target neurological structure 1165, perhaps connecting oneor more structures 1170 in the vicinity of the lumen 1160 to one or moreexternal organs, ganglia, or the like, that are somewhat removed fromthe lumen 1160 may be targeted as well during such procedures. Inaspects, sensing tips included in the micro surgical tool may have beenused to track the targeted tissues as the surgical process is occurring(so as to establish a treatment path in the vicinity of the targettissues), locate target tissues for treatment, monitor the treatmentprocess itself, to avoid unintentional treatment of nerve bundles thatare not to be surgically treated, to confirm effective treatment, and tolimit the overall amount of damage caused by the treatment procedure. Inthis non-limiting example, the target anatomical structures 1165, 1167,1169 are treated along one or more pathways 1177, 1182, 1187 as followedwith guidance from one or more of the sensing tips (or via collectivelocal treatment by a collection of sensing tips). Such stretches andstrategic placement of treatment zones 1175, 1180, 1185 may be employedto limit the potential for regeneration after the surgical procedure hasbeen completed. In aspects, feedback from signals obtained from one ormore sensing tips may be used to guide the surgical hardware during thesurgical procedure (i.e. ablation, chemical substance delivery,cryoablation, energy delivery, abrasion, etc.).

FIG. 12a shows a schematic diagram of a micro surgical tool 1210deployed at a surgical site in accordance with the present disclosure.The micro surgical tool 1210 is shown deployed into a renal artery 1202of a subject having passed through a superior or inferior approach(brachial or femoral arteries), via aortic artery 1205 and into therenal artery 1202 (or to the mouth thereof). The micro surgical tool1210 includes a delivery catheter 1224 and a microfinger array 1212 inaccordance with the present disclosure, shown in contact with the wallsof the renal artery 1203 (i.e. biased towards, in controlled contactwith, penetrating into, etc.). Connected to the microfinger array 1212via a guiding arm 1215 is a local control circuit 1220 in accordancewith the present disclosure. In aspects, the guiding arm 1215 mayinclude one or more electrical interconnects, one or more structuralelements, a conduit, or the like coupled to the microfinger array 1212and/or the local control circuit 1220. The control circuit 1220 mayroute signal traffic to and from the microfinger array 1212, etc. Theschematic further depicts application of RF current 1221 applied locallybetween sensing tips in the microfinger array 1212 as well as analternative RF current 1223 between one or more sensing tips in themicrofinger array 1212 and an external electrode (not explicitly shown).The catheter 1224 may be coupled to an operator 1226, a controller, asignal conditioning circuit, or the like for controlling the microfingerarray 1212 during a procedure. In aspects, the microfinger array 1212may be advanced and/or retracted 1227, along the lumen 1203 and/orrotated 1229 around the circumference of the lumen 1203 duringprocedures related to searching for anatomical sites of interest,performing sensing, mapping, surgical treatments, ablation, or the like.

FIG. 12b shows a schematic diagram of a micro surgical tool 1230deployed at a surgical site in accordance with the present disclosure.The micro surgical tool 1230 is shown deployed into a renal artery 1202of a subject having passed through a superior or inferior approach(brachial or femoral arteries), via aortic artery 1205 and into therenal artery 1202 (or to the mouth thereof). The micro surgical tool1230 includes a delivery catheter 1232 and a microfinger array 1234 inaccordance with the present disclosure, shown in contact with the wallsof the renal artery 1203 (i.e. biased towards, in controlled contactwith, penetrating into, etc.). In this, non-limiting example, themicrofinger array 1234 is configured as a longitudinal wire cage inaccordance with the present disclosure. Such a configuration may beadvantageous to maintain contact with the lumen walls during a procedurewithout inhibiting flow of fluids through lumen. Connected to themicrofinger array 1234 via a guiding arm 1238 is a local control circuit1236 in accordance with the present disclosure. In aspects, the guidingarm 1238 may include one or more electrical interconnects, one or morestructural elements, a conduit, or the like coupled to the microfingerarray 1234 and/or the local control circuit 1236. The micro-surgicaltool 1230 is also configured to accommodate, or includes a guide wire1240 configured to assist with guiding the microfinger array 1234 to thetarget anatomical site. The microfinger array 1234 may be coupled to adistal ringlet 1241 or equivalent feature, configured to accommodate thepassage of the guide wire 1240 there through during the procedure. Inaspects, the control circuit 1236 may route signal traffic to and fromthe microfinger array 1234, etc. The schematic further depictsapplication of RF current 1243 applied locally between sensing tips inthe microfinger array 1234 as well as an alternative RF current 1245between one or more sensing tips in the microfinger array 1234 and anexternal electrode (not explicitly shown). The catheter 1236 and/orguiding arm 1238 may be coupled to an operator 1226, a controller, asignal conditioning circuit, or the like for controlling the microfingerarray 1234 during a procedure. In aspects, the microfinger array 1234may be advanced and/or retracted 1247, along the lumen 1203 and/orexpanded/contracted 1249 as part of a procedure, a deployment, and/or aretraction procedure within the lumen 1203 during procedures related tosearching for anatomical sites of interest, performing sensing, mapping,surgical treatments, ablation, or the like.

FIG. 12c shows a schematic diagram of a micro surgical tool 1250deployed at a surgical site in accordance with the present disclosure.The micro surgical tool 1250 is shown deployed into a renal artery 1202of a subject having passed through a superior or inferior approach(brachial or femoral arteries), via aortic artery 1205 and into therenal artery 1202 (or to the mouth thereof). The micro surgical tool1250 includes a delivery catheter 1258 and a plurality of microfingerarrays 1252, 1254 each in accordance with the present disclosure, shownin contact with the walls of the renal artery 1203 (i.e. biased towards,in controlled contact with, penetrating into, etc.). In this,non-limiting example, the microfinger arrays 1252, 1254 are configuredas a radially biased flexural springs, in accordance with the presentdisclosure. Such a configuration may be advantageous to maintain contactwith the lumen walls during a procedure without inhibiting flow offluids through lumen, to accommodate a wide range of anatomicalfeatures, to maintain a relatively constant bias force on the lumenwalls 1203 during a procedure, for simple deployment/retraction,combinations thereof, or the like. Connected to the microfinger arrays1252, 1254 via one or more guiding arms 1256, 1257 is a local controlcircuit 1260 in accordance with the present disclosure. In aspects, theguiding arm(s) 1256, 1257 may include one or more electricalinterconnects, one or more structural elements, a conduit, or the likecoupled to the microfinger arrays 1252, 1254 and/or the local controlcircuit 1260. The micro-surgical tool 1250 may also be configured toaccommodate, and/or include a guide wire (not explicitly shown)configured to assist with guiding the microfinger arrays 1252, 1254 tothe target anatomical site. In aspects, one or more of the guiding arms1256, 1257 may be configured so as to retract and or advance along themicrosurgical tool 1250 with respect to the microfinger arrays 1252,1254 so as to cover and/or expose one or more of the microfinger arrays1252, 1254 during a retraction and/or deployment process. In aspects,the control circuit 1260 may route signal traffic to and from one ormore of the microfinger arrays 1252, 1254, etc. The schematic furtherdepicts application of RF current 1261 applied locally between sensingtips in the microfinger arrays 1252, 1254 as well as an alternative RFcurrent 1263 between one or more sensing tips in the microfinger arrays1252, 1254 and an external electrode (not explicitly shown). Thecatheter 1260 and/or guiding arm(s) 1256, 1257 may be coupled to anoperator 1226, a controller, a signal conditioning circuit, or the likefor controlling the microfinger arrays 1252, 1254 during a procedure. Inaspects, the microfinger arrays 1252, 1254 may be advanced and/orretracted 1265, along the lumen 1203 and/or deployed or retracted bymovement 1267 of one or more guiding arms 1256, 1257 during deployment,and/or a retraction procedure within the lumen 1203 during proceduresrelated to searching for anatomical sites of interest, performingsensing, mapping, surgical treatments, ablation, or the like. Inaspects, the microsurgical tool 1250 may be advanced after deployment ofthe microfinger arrays 1252, 1254 so as to strongly bias and/orpenetrate one or more sensing tips in the microfinger arrays 1252, 1254into the wall 1203 of the lumen 1205 during a procedure.

FIG. 12d shows a schematic diagram of a micro surgical tool 1270deployed at a surgical site in accordance with the present disclosure.The micro surgical tool 1270 is shown deployed into a renal artery 1202of a subject having passed through a superior or inferior approach(brachial or femoral arteries), via aortic artery 1205 and into therenal artery 1202 (or to the mouth thereof). The micro surgical tool1270 includes a delivery catheter 1272 and a plurality of sensing tips1274 arranged over a balloon 1275 each in accordance with the presentdisclosure, shown in contact with the walls of the renal artery 1203(i.e. biased towards, in controlled contact with, penetrating into,etc.). In this, non-limiting example, one or more of the sensing tips1274 maybe arranged along the balloon 1275 walls so as to contact thelumen wall 1203 during and/or after deployment. Such a configuration maybe advantageous for isolating one or more of the sensing tips 1274 fromthe fluid which would normally flow through the lumen 1202. Connected tothe balloon 1275 and one or more of the sensing tips 1274, via a guidingarm 1277 is a local control circuit 1280 in accordance with the presentdisclosure. In aspects, the guiding arm 1277 may include one or moreelectrical interconnects, one or more structural elements, a conduit fordelivery/removal of fluid to/from the balloon 1275, or the like coupledto the sensing tips 1274 and/or the local control circuit 1280. Themicro-surgical tool 1270 may also be configured to accommodate, and/orinclude a guide wire (not explicitly shown) configured to assist withguiding the balloon 1275 to the target anatomical site. In aspects, theballoon 1275 and/or guiding arm 1277 may be coupled to a distal ringlet1282 or equivalent feature, configured to fasten the balloon to theguiding arm 1277 and/or to accommodate the passage of the guide wire1240 there through during the procedure. In aspects, the guiding arm1277 may be configured so as to retract and or advance along themicrosurgical tool 1270 with respect to the balloon 1275 so as to coverand/or expose one or more of the sensing tips 1274 during a retractionand/or deployment process. In aspects, the control circuit 1280 mayroute signal traffic to and from one or more of the sensing tips 1274,etc. The schematic further depicts application of RF current 1281applied locally between sensing tips 1274 as well as an alternative RFcurrent 1283 between one or more sensing tips 1274 and an externalelectrode (not explicitly shown). The catheter 1272 and/or guiding arm1277 may be coupled to an operator 1226, a controller, a signalconditioning circuit, or the like for controlling the sensing tips 1274during a procedure. In aspects, the balloon 1275 may be repositioned1285 along the lumen 1203 and/or expanded or contracted 1287 duringdeployment, and/or a retraction procedure within the lumen 1203 duringprocedures related to searching for anatomical sites of interest,performing sensing, mapping, surgical treatments, ablation, or the like.

FIG. 13 shows a schematic diagram of interaction between one or moremacroelectrodes 1302, 1304, 1306 (i.e. not limited to three, could be arange of possibilities) and a micro surgical tool 1310 deployed at asurgical site in accordance with the present disclosure. The abdomen1301 of a subject is shown with an internally placed micro surgical tool1310 (dotted line) located with the tip 1315 in a renal artery of thesubject. When a suitable target site for an ablation process isdetermined, the electrical impedance (e.g. DC impedance, AC impedance,real, imaginary, complex impedance spectra, etc.) between elements ofthe network formed by one or more sensing tips 1315 included in themicro surgical tool 1310, one or more macroelectrodes 1302, 1304, 1306placed on the body of the patient, pushed up against the patient,located along the catheter wall of the micro surgical tool, placedwithin the patient (perhaps endoscopically, via a catheterizationprocedure, etc.) may be monitored. Such relational impedancemeasurements are depicted diagrammatically with arrows 1321, 1323, 1325,1331, 1333, 1335 between elements 1302, 1304, 1306, 1310, 1315 of thenetwork in FIG. 13.

Based upon the impedances in the associated network, an RF ablationcurrent may be applied between two or more elements 1301, 1304, 1306,1310, 1315 thereof. In one non-limiting example, each element 1301,1304, 1306, 1310, 1315 of the network may include a controllableimpedance circuit. The impedance control circuits may be used to draw aportion of the RF current into/out of the associated element 1301, 1304,1306, 1310, 1315. In this sense, local control of the RF current at thesensing tips 1315 may be more precisely controlled. Electric fieldstrengths, current flow, etc. may be monitored at any element 1301,1304, 1306, 1310, 1315 of the network so as to determine the RF currentflow path into the local tissues of the target anatomy (i.e. into a wallof a lumen, a renal artery, etc.).

FIG. 14 shows a micro balloon catheter 1410 deployed at a surgical sitein accordance with the present disclosure. In this non-limiting example,the micro balloon catheter 1410 is shown deployed into a renal artery1402 of a subject having passed through a superior or inferior approach(brachial or femoral arteries), via aortic artery 1405 and into therenal artery 1402 (or to the mouth thereof). The micro balloon catheter1410 is shown with a layer of indicating agents 1415 and/or contrastagent coated onto the balloon 1420 thereof. The micro balloon catheter1410 is shown as placed within the renal artery 1402 of a subject, in aninflated state. In this state, the indicating agents 1415 and/orcontrast agents are released 1419 (i.e. via diffusion, active transport,etc.) into the surrounding tissues for later use during a surgicalprocedure. In aspects, the micro balloon catheter 1410 may include oneor more sensory tips, a delivery catheter 1422, a guiding arm 1424,coupled to the balloon 1420 in accordance with the present disclosure.The catheter 1422 may be coupled to an operator 1426, a controller, asignal conditioning circuit, or the like for controlling the balloon1420 during a procedure. In aspects, the indicating agent 1415 may beconfigured so as to change chromatic and/or photochemical properties inthe presence, when bound to, or when incorporated into the targetanatomy.

FIGS. 15a-b show aspects of non-limiting examples of opticalmicrosensing tips 1510 and a collective response therefrom in accordancewith the present disclosure. FIG. 15a shows an array of opticalmicrosensing tips 1510 biased towards the wall 1501 of a vessel. Theoptical microsensing tips 1510 are configured to receive from and/oremit energy into the adjacent tissues of the wall 1502. In aspects, anexternal light source 1515 may also provide light towards the surgicalsite (i.e. vessel walls 1502). In aspects, energy 1520 passing throughan anatomical site of interest 1503 may be accepted by one or more ofthe optical microsensing tips 1510, each configured to generate a signaltherefrom. In aspects, the microsensing tips 1510 may include a fiberoptic element coupled to a remote light source and/or photodetector.Such a configuration may be coupled with the indicating agents describedin FIG. 15 (i.e. so as to locate the target anatomy as part of asurgical procedure). In aspects, the indicating agent 1415 may beconfigured so as to change chromatic and/or photochemical properties inthe presence, when bound to, or when incorporated into the targetanatomy 1503, thus being detectable by one or more optical microsensingtips 1510.

FIG. 15b shows a spectral response of the light received by the opticalmicrosensing tips 1510 and that emitted by an external light source. Thedetected signals 1535, 1540 may be used to determine the location oftarget tissues in the vessel wall. In aspects, the optical microsensingtips 1510 may include one or more electrode elements so as toselectively and locally ablate target tissues based on the response ofthe sensed signals 1535, 1540.

FIG. 16 shows a combination catheterization and endoscopic procedure ona renal artery in accordance with the present disclosure. A microsurgical tool 1610 in accordance with the present disclosure is shown asplaced into the renal artery of a subject. One or more endoscopicallyplaced light sources 1615, 1617 may be shone at the renal artery. Inaspects, the light sources 1615, 1617 may be multi-band sources,broadband sources, narrow band sources, modulated, or any combinationthereof. In aspects, the micro surgical 1610 tool may include one ormore optical microsensors to receive such light, the processed signalsused to determine the location of target tissues in the renal artery. Inaspects, the microsurgical tool 1610 may include one or more sensingtips in accordance with the present disclosure to selectively treattarget anatomy based on the determined locations thereof. An optionalendoscopically placed camera 1620 is also shown. In aspects, the camera1620 may include a light source. The camera 1620 may be used as part ofa feedback mechanism to control placement of the micro surgical tool1610 in the renal artery. In aspects, the camera 1620 may use a range oflight sources to elicit placement information of target anatomy (perhapsin combination with indicating/contrast agents in accordance with thepresent disclosure), placement of the micro surgical tool 1610 withinthe renal artery, and/or monitoring of the surgical procedure (i.e.ablation procedure, chemical denervation, chemical deployment, etc.).Such a feedback mechanism may be used to precisely guide the microsurgical tool 1610 during a surgical procedure (i.e. ablation procedure,etc.). In one non-limiting example the camera 1620 and/or a light source1615, 1617 may include a macroelectrode in accordance with the presentdisclosure.

FIG. 17a shows a schematic diagram of aspects of a micro surgical toolin accordance with the present disclosure. The micro surgical toolincludes a plurality of microfingers 1710 equipped with sensing tips1715 in accordance with the present disclosure, a local control circuit1720 (optionally located near to the tip of the micro surgical tool) inaccordance with the present disclosure, and a guiding arm 1726 and adelivery catheter 1724 to connect, both mechanically and electricallythe tip of the tool to an operator, robot, etc. In aspects, the localcontrol circuit 1720 may be located at the operating end of the catheter1724 (i.e outside the body of a subject during use). Alternatively,additionally, or in combination a control circuit 1720 may be coupled tothe microfingers 1710 directly, or via the guiding arm 1726 in order tocommunicate signals to or from the sensing tips 1715 during a procedure.In aspects, the microfingers 1710 may be configured so as to bend withinthe body of a subject (i.e. after a deployment process, etc.) so as tobias toward the walls of the anatomy of interest, etc. In aspects, themicrofingers 1710 may be directed (i.e. like a pencil) towards the wallof an organ, and/or anatomical feature so as to form a plurality ofmicrocontacts at each sensing tips, for the purposes of mapping,sensing, performing a treatment, etc. thereupon.

FIG. 17b shows a schematic diagram of aspects of a micro surgical toolin accordance with the present disclosure. The micro surgical toolincludes a plurality of microfinger arrays 1730 a-b equipped withsensing tips 1731 a-b, a guiding arm 1732, and a delivery catheter 1734each in accordance with the present disclosure. In aspects, the guidingarm 1732, one or more microfingers 1730 a-b, and/or the catheter 1734may include a control circuit in accordance with the present disclosure.In aspects, a local control circuit 1720 in accordance with the presentdisclosure may be located at the operating end of the catheter 1734 (i.eoutside the body of a subject during use). Alternatively, additionally,or in combination a control circuit may be coupled to one or more of themicrofingers 1730 a-b directly, or via the guiding arm 1732 in order tocommunicate signals to or from the sensing tips 1731 a-b during aprocedure. In aspects, the microfinger arrays 1730 a-b may be configuredso as to bend within the body of a subject (i.e. after a deploymentprocess, etc.) so as to bias toward the walls of the anatomy ofinterest, etc. In aspects, one or more of the microfingers 1730 a-b maybe configured so as to bend when heated to body temperature (i.e. so asto self-deploy during a procedure). In aspects, the guiding arm 1732and/or the catheter 1734 (and/or a sleeve thereupon) may be retracted1736 to initiate a deployment process so as to expose one or more of themicrofingers 1730 a-b and bring them into contact with the intendedanatomy. In aspects, one or more sensing tips 1731 a-b may be equippedwith one or more electrodes for electrophysiological sensing,stimulation, and/or RF current delivery to the surrounding tissues. Thussignals may be monitored between 1738 sensing tips 1731 a-b in differentmicrofinger arrays 1730 a-b or within 1739 the same microfinger array1730 a, 1730 b. In aspects, the guiding arm 1732 and/or catheter 1734may be adjustable so as to adjust the distance between microfingerarrays 1730 a-b in the micro surgical tool tip.

FIG. 17c shows a schematic diagram of aspects of a micro surgical toolin accordance with the present disclosure. The micro surgical toolincludes a longitudinal wire cage including a plurality of microfingers1740 a-b, with regions coupled to sensing tips 1742 a-f in accordancewith the present disclosure. Such a configuration may be advantageous tomaintain contact between one or more sensing tips 1742 a-f with thelumen walls during a procedure without inhibiting flow of fluids throughlumen. In aspects, the micro-surgical tool may be configured toaccommodate, or to include a guide wire (not explicitly shown)configured to assist with guiding wire cage to the target anatomicalsite. In aspects, the wire cage may be coupled to a distal ringlet 1750or equivalent feature, configured to accommodate the passage of a guidewire there through during the procedure. The schematic further depictsapplication of RF current 1752 applied locally between sensing tips 1742e,f in the wire cage. The wire cage may be coupled to a deliverycatheter 1754, perhaps coupled as a sleeve that can extend over the wirecage so as to force collapse thereof. In aspects, retraction 1760 of thedelivery catheter 1754 may be used to deploy the wire cage during aprocedure. The catheter 1754 and/or an enclosed guiding arm (notexplicitly shown) may be coupled to an operator, a controller, a signalconditioning circuit, or the like for controlling the sensing tips 1742a-f, and/or the wire cage during a procedure. In aspects, the wire cagemay be advanced and/or retracted, along a lumen (not explicitly shown)and/or expanded/contracted as part of a procedure, a deployment, and/ora refraction procedure within the lumen during procedures related tosearching for anatomical sites of interest, performing sensing, mapping,surgical treatments, ablation, or the like.

In aspects, one or more sensing tips 1742 a-f may be equipped with oneor more electrodes for electrophysiological sensing, stimulation, and/orRF current delivery to the surrounding tissues. Thus signals may bemonitored between sensing tips 1742 a-f, between a sensing tip 1742 a-fand an external electrode, etc.

In aspects, one or more sensing tips 1742 a-f may be arrangedlongitudinally along the axis of the microsurgical tip, such that thesensing tips 1742 a-f are biased against a lumen wall at site spacedalong the longitudinal direction thereof upon deployment.

FIGS. 18a-f show aspects of non-limiting examples of micro surgicaltools in accordance with the present disclosure.

FIG. 18a shows a microfinger array in accordance with the presentdisclosure. The array includes five microfingers 1810 each equipped withone or more sensory tips 1815 in accordance with the present disclosure.The microfingers 1810 and associated sensing tips 1815 are shown biasedagainst a tissue surface 1801. Interaction between two of the sensingtips 1815 is depicted with an arrow 1820 in the diagram.

FIG. 18b shows a time series of data collected by several sensing tips1815 in the microfinger array 1810. The neurological activity 1825 of alocal tissue site is monitored 1827. At a ablation start time 1826, anablation current 1829 is sent through one or more sensing tips 1815 andan altered neurological activity 1831 is confirmed afterwards.

FIG. 18c shows an aspect of a mesh-like array 1840 of interwoven wires1842 (i.e. microfingers in accordance with the present disclosure), withassociated sensing tips 1844. The sensing tips 1844 may be arranged suchthat they contact the local tissues 1802 when the mesh 1840 is biasedagainst the tissue 1802. In one non-limiting example, the mesh-likearray 1840 may be formed from an interwoven group of superelastic wires(e.g. Nitinol wires, spring steel wires, etc.). The mesh 1840 may beformed as a sock, webbing, an arched structure, a donut, a net, etc.Upon deployment to the surgical site, the mesh 1840 may expand so as tocontact the local tissues 1802 of interest. Electrical interconnects forthe sensing tips 1844 may be provided via the wires 1842, routed alongthe wires 1842, etc. In on non-limiting example, substrates inaccordance with the present disclosure may be interwoven instead of thewires 1842 as shown. Such substrates may be used to form a deployablemesh like structure complete with electrical interconnects, sensing tips1844, distributed integrated circuits, etc.

FIG. 18d shows aspects of a net like micro surgical tool in accordancewith the present disclosure. The net like structure 1850 may be formedfrom one or more fibers, wires, ribbons, etc. Additionally,alternatively, or in combination the one or more net like structures1850 may include a substrate in accordance with the present disclosure(e.g. a porous substrate material such as a silk structure, anelastomer, polymer, netting, fabric, fiber composite, etc.). In onenon-limiting example, a silk-flexcircuit composite may form the net likestructure 1850. In this example, the flexcircuit may be formed frommaterials as known to those skilled in the art, the flex circuit may beconstructed such that substantial material, not occupied by electricalinterconnects is removed (thus forming a loosely connected webbing offlexcircuit elements). The flexcircuit may thus be formed in anexcessively thin form (e.g. less than 25 um, less than 10 um, less than4 um, less than 1 um thick). A supporting material such as silk may beused to complete the substrate and form a functional, robust net likestructure 1850 included in the micro surgical tool. The net likestructure may be interconnected 1852 to a delivery catheter, anoperator, a controller, one or more control circuits, etc. each inaccordance with the present disclosure.

The micro surgical tool may include or be coupled with a micro balloon,the micro balloon configured so as to bias the net up against the localtissues 1803.

FIG. 18e shows a stent-like deployable micro surgical tool in accordancewith the present disclosure. The stent-like micro tool 1862 may includea plurality of sensing tips 1860 electrically interconnected with theremainder of the micro surgical tool. The sensing tips 1860 may bepositioned throughout the stent-like micro tool 1862. In onenon-limiting example, the sensing tips 1860 may be generally positionedtowards the end of the tool. The stent-like micro tool may beinterconnected to a guiding arm 1864 for connection 1865 to an operator(not explicitly shown), controller, etc.

The stent-like micro tool may be inserted into a lumen 1804 past theintended surgical site. It may then be deployed so as to expand outwardsand make contact with the lumen walls 1804. The micro-tool may then bedragged 1865 forward, sweeping along the walls of the vessel. In onenon-limiting example, the sensing tips 1860 may be configured to monitorphysiologic parameters during this initial sweep (e.g. so as to map thelocal tissue properties). After the first sweep, the tool 1862 may beretracted and once again placed beyond the intended surgical site. Itmay then be deployed so as to expand outwards and make contact with thesurgical site. The tool 1862 may then be dragged forward, sweeping alongthe walls of the vessel for a second time. During this second sweep, thesensing tips 1860 may be activated to locally ablate tissue atpredetermined locations determined by the initial sweep. Sensory tips1860 may further be monitored during ablation processes to ensure thatthe processes are sufficiently completed before further sweeping thestent-like micro tool 1862 though the vessel.

In another non-limiting example the stent-like micro tool 1862 may beinserted past the intended surgical site. It may then be deployed so asto expand outwards and make contact with the lumen wall 1804. Themicro-tool 1862 may then be dragged forward, sweeping along the walls ofthe vessel 1804. The sensing tips 1860 may, in concert, monitor thelocal physiologic properties of the tissues and selectively activated tolocally ablate tissues. Thus both the functions of monitoring andablation may be completed in a single sweep.

The stent-like micro tool 1862 may include any features described hereinas they pertain to a microfinger in accordance with the presentdisclosure.

FIG. 18f shows a two dimensional graph, indicating the ablation profileof 5 sensing tips located in a stent-like micro tool in accordance withthe present disclosure. The desired ablation profile may bepredetermined (e.g. as determined by an initial sweep), or determined inconcert during a sensing+ablation sweep. As can be seen in the exampleshown, two of the sensing tips did not pass any target tissue in need ofablation during this sweep, thus an ablation procedure may be directedtowards other sensing tips in the array so as to minimize damage tolocal tissues during the procedure.

FIGS. 19a-b show a tonal sensing tip and sample response in accordancewith the present disclosure. FIG. 19a shows a close up of an associatedmicrofinger 1910 in accordance with the present disclosure. Themicrofinger 1910 includes an interfacial pressure sensor (at the tip, inaccordance with the present disclosure) and/or a flexural sensor (alongthe length thereof, in accordance with the present disclosure). Anexcitation 1915, 1920, 1925 applied to the microfinger 1910 may be usedto generate variable contact forces and contact deflections at the pointof contact between the microfinger and a local tissue surface 1901.Signals obtained from the flexural sensor may be representative of thecontact deflections that occur during the excitation period. Signalsobtained from the interfacial pressure sensor may be representative ofthe contact forces that occur during the excitation period. Thesimultaneous monitoring of both signals, perhaps in combination with acompliance model for the microfinger 1910 may be useful for determiningthe local mechanical properties of the tissue in the vicinity of thecontact point.

FIG. 19b shows a deflection force curve, generated by the microfinger1910 described in FIG. 19a during an excitation session. Thedeflection/force relationships (e.g. mean relationships, hysteresis,frequency dependence, creep, strain hardening, etc.) may be used todetermine the type of tissues 1901 in which the microfinger is incontact. As can be seen in the figure, a particularly soft relationship1930 (low modulus of elasticity) may be associated with a potentialtumor tissue. Healthy tissue may exhibit a modulus of elasticity withina known “good” range 1935, and the trend 1950 in elastic modulus thatoccurs as the tissue is ablated by a surgical procedure, may be followedto determine the extent of the ablation process. A successful ablationprocess may be qualified by a range of elastic modulus change 1940, asobserved during the ablation process.

FIGS. 20a-b show aspects of surgical tools in accordance with thepresent disclosure. FIG. 20a shows a surgical tool including a deliverycatheter 2005 in accordance with the present disclosure including anarray of microfingers 2010, the microfingers 2010 connected 2011 throughthe catheter 2005 to an operating fixture, control circuit, signalconditioning circuit, hand held control unit, surgical robot, acoupling, or the like. The microfingers 2010 in accordance with thepresent disclosure are arranged along the inside of the deliverycatheter 2005 and are arranged with a pre-biased shape, such that uponretraction 2021 of the catheter 2005, the microfingers 2010 may bedeployed radially 2119 towards an anatomical site of interest (i.e. asurgical site, a tissue surface, a lumen wall, etc.). One or more of themicrofingers 2010 may include one or more sensing tips 2015 inaccordance with the present disclosure. In the non-limiting exampleshown, each sensing tip includes an electrode configured to interfacewith an anatomical site of interest. The catheter 2005 is configured toslide over an associated guide wire 2030, so as to be easily directed toa surgical site during an insertion procedure. In the non-limitingexample shown, the microfingers 2010 include shaped tips (upon which thesensing tips 2015 are arranged). Such shaped tips may be advantageous tocontrol the bias pressure against an anatomical site of interest (i.e.so as to prevent penetration, etc.). In aspects, one or more of themicrofingers 2010 may terminate at a microneedle sensing tip inaccordance with the present disclosure. Such a configuration may beadvantageous to allow for controlled penetration of one or more sensingtips 2015 into the wall of a surgical site. In aspects, afterdeployment, the entire microfinger array 2010 may be drawn 2023 alongthe length of a lumen, so as to map the lumen, sweep monitor and ablatethe lumen, assess the state of anatomy after a surgical procedure,combinations thereof, or the like.

FIG. 20b shows catheter 2005 in accordance with the present disclosureincluding a longitudinal wire cage including an array of microfingers2010, the microfingers 2050 connected 2053 through a delivery catheter2054 to an operating fixture, control circuit, signal conditioningcircuit, hand held control unit, surgical robot, a coupling, or thelike. The microfingers 2050 in accordance with the present disclosureare arranged along the inside of the delivery catheter 2054 with a rangeof pre-biased shapes, such that upon retraction 2056 of the deliverycatheter 2054 or an over sheath coupled thereto, the microfingers 2050may be deployed radially 2057 towards an anatomical site of interest(i.e. a surgical site, a tissue surface, a lumen wall, etc.) to form thewire cage. One or more of the microfingers 2050 may include one or moresensing tips 2051 in accordance with the present disclosure. In thenon-limiting example shown, each sensing tip includes an electrodeconfigured to interface with an anatomical site of interest. Thecatheter 2054 is configured to slide over an associated guide wire 2060,so as to be easily directed to a surgical site during an insertionprocedure. In aspects, the wire cage may be coupled to a distal ringlet2062 or equivalent feature, configured to accommodate the passage of aguide wire there through during the procedure.

In aspects, the microfingers 2050 may be arranged such the sensing tips2051 are arranged so as to contact the lumen wall upon deployment.

Such a configuration may be advantageous to maintain contact between oneor more sensing tips 2051 with the lumen walls during a procedurewithout inhibiting flow of fluids through lumen. In aspects, the wirecage may be advanced and/or retracted, along a lumen (not explicitlyshown) and/or expanded/contracted as part of a procedure, a deployment,and/or a retraction procedure within the lumen during procedures relatedto searching for anatomical sites of interest, performing sensing,mapping, surgical treatments, ablation, or the like.

In aspects, one or more sensing tips 2051 may be equipped with one ormore electrodes for electrophysiological sensing, stimulation, and/or RFcurrent delivery to the surrounding tissues.

In aspects, one or more sensing tips 2051 may be arranged longitudinallyalong the axis of the microsurgical tip, such that the sensing tips 2051are biased against a lumen wall at site spaced along the longitudinaldirection thereof upon deployment.

FIG. 21 shows aspects of a system for performing a surgical procedure inaccordance with the present disclosure. The system is shown interfacingwith a surgical site 2101 within a body, a subject, a patient, etc. Thesystem includes a microsurgical tool 2110 in accordance with the presentdisclosure. During use, the microsurgical tool 2110 is configured tointeract 2112 with the surgical site 2101 in accordance with the presentdisclosure. In aspects, the microsurgical tool 2110 may be coupled to aconnector 2120, the connector providing a mechanical and electricalinterface between the microsurgical tool 2110 and one or more othermodules of the system. In aspects, the microsurgical tool may include anembedded local control circuit 2115 a (a microcircuit, a switch network,a signal conditioning circuit, etc.) in accordance with the presentdisclosure. In aspects, the connector 2120 may include a local controlcircuit 2115 b in accordance with the present disclosure. In aspects,the connector 2120 may be coupled to an operator input device 2125 (i.e.a foot pedal, an advancing slider, a torqueing mechanism, a recordingbutton, an ablation button, etc.). In aspects, the connector 2120 may becoupled to a control unit 2130 configured to accept one or more signalsfrom the microsurgical tool 2110, communicate one or more controlsignals thereto, send one or more pulsatile and/or radio frequencysignals to the microcontroller, record one or more electrophysiologicalsignals from the microsurgical tool, or the like.

In aspects, the control unit 2130 may be connected to a display 2135configured to present one or more aspects of the recorded signals fromthe microsurgical tool to an operator, to present a map, at leastpartially dependent on the recorded signals, etc.

In aspects, the control unit 2130 may be coupled to a surgical subsystem2140, the surgical subsystem 2140 configured to perform a surgicalprocedure 2145 to the surgical site 2101. Some non-limiting examples ofsuitable surgical procedures include an ablation, an excision, a cut, aburn, a radio frequency ablation, radiosurgery, an ultrasonic ablation,an abrasion, a biopsy, and delivery of a substance. The control unit2130 may be configured to influence, direct, control, and/or providefeedback for one or more aspects of the surgical procedure 2140, basedupon one or more of the electrophysiological signals conveyed by themicrosurgical tool 2110.

In aspects, the microsurgical tool 2110 includes means for monitoringone or more physiologic parameters in accordance with the presentdisclosure.

FIGS. 22a, b further illustrate aspects of systems and methods inaccordance with the present disclosure.

FIG. 22a illustrates aspects of a system and/or procedure fordetermining the extent of a denervation procedure. An organ 2203 (e.g. akidney, etc.) is shown with associated lumen 2205 (i.e. artery, vein,ureter, etc.), one or more nerves passing in close proximity to thelumen 2205 between a central nervous system and the organ 2203. FIG. 22aalso illustrates a first region 2225 and a second region 2230 locatedalong the length of the lumen 2205, the first region 2225 equidistant toor farther from the organ 2203 than the second region 2230. FIG. 22afurther illustrates a means for measuring, monitoring 2235, orevaluating a change in a physiologic parameter 2201 in accordance withthe present disclosure, blood pressure, sympathetic tone, vessel wallstiffness, combinations thereof, or the like (i.e. such as via apressure sensor, a blood pressure cuff, a finger cuff, a blood pressuresensing catheter, a microsurgical tool 2110 in accordance with thepresent disclosure, etc.).

FIG. 22b illustrates aspects of a system and/or procedure fordetermining the extent of a denervation procedure. An organ 2203 (e.g. akidney, etc.) is shown with associated lumen 2205 (i.e. artery, vein,ureter, etc.), one or more nerves passing in close proximity to thelumen 2205 between a central nervous system and the organ 2203. FIG. 22balso illustrates a first region 2250 and a second region 2255 locatedalong the length of the lumen 2205, the first region 2250 equidistant toor farther from the organ 2203 than the second region 2255. FIG. 22bfurther illustrates a means for measuring, monitoring 2285, orevaluating a change in a physiologic parameter 2201 in accordance withthe present disclosure, blood pressure, sympathetic tone, vessel wallstiffness, combinations thereof, or the like (i.e. such as via apressure sensor, a blood pressure cuff, a finger cuff, a blood pressuresensing catheter, a microsurgical tool 2110 in accordance with thepresent disclosure, etc.).

FIG. 22b illustrates a schematic diagram of a tool 2265 in accordancewith the present disclosure configured to perform a procedure on thefirst region 2250 or second region 2255 in close proximity to the lumen2205. The tool 2265 includes a distal region 2260 configured forperforming the procedure, stimulating, sensing, ablating, monitoring oneor more of the physiologic parameters 2201, or the like in accordancewith the present disclosure. The surgical tool 2265 may include a secondregion 2270 including a sensor in accordance with the present disclosureconfigured to monitor one or more of the physiologic parameters 2201.

In aspects, one or more steps of a method in accordance with the presentdisclosure may be performed by the surgical tool 2265. In aspects, thesurgical tool 2265 may be a microsurgical tool 2110 in accordance withthe present disclosure. The monitoring 2285 information, energydelivery, chemical delivery, coordination between sensing/treatmentaspects of the tool may be coupled with a controller 2130, a display2135 or the like.

In aspects, the surgical tool may include one or more sensing tips,micro fingers, or the like each in accordance with the presentdisclosure. The tips, microfingers, or the like may be arranged such atthat one or more may interface with tissues in the vicinity of the firstregion 2250 or the second region 2255 either with a single placement ofthe tool within the lumen 2205, or when upon repositioning the tipwithin the lumen 2205 (i.e. the tips, fingers, etc. may be distributedalong the length of the lumen, position able within the lumen, etc.). Inaspects, the surgical tool may include a balloon in accordance with thepresent disclosure, the balloon including one or more energy deliveryelements (i.e. electrodes, thermal heating elements, etc.), and/orchemical delivery elements (i.e. for delivery of a chemical substanceinto an adjacent tissue), arranged along the length of the balloon andoptionally around the circumference of the balloon. In aspects one ormore energy or chemical delivery elements, tips, microfingers or thelike, may be substantially independently operable so as to interfacewith one or more sites near or within the first region 2250, and/or thesecond region 2255 during use.

In aspects, the first region 2225, 2250 and/or the second region 2230,2255 may be arranged so as to substantially surround the lumen 2205(i.e. so as to form a region through which the lumen 2205 passes).

A method in accordance with the present disclosure for determining theprogression of a procedure may include performing a procedure on thefirst region 2225, 2250 (i.e. energy application to, ablation of tissuesin the vicinity of, delivery of a chemical to, etc.), applying follow onprocedure to the second region 2230, 2255 (i.e. stimulating, performinga procedure thereupon, applying energy thereto, etc.), and monitoring2235, 2285 one or more physiologic parameters 2201 (e.g. such as bloodpressure). The procedure applied to the first region 2225, 2250 wassuccessfully completed if the physiologic parameter(s) 2201 does notchange after applying the follow on procedure to the second region 2230,2255. In aspects, the method may include monitoring 2235, 2285 thephysiologic parameter for a period of 5 s, 30 s, 1 min, 3 min, 5 min, 8min after the application of the follow on procedure to the secondregion 2230, 2255.

In aspects, the method may include application of an excitotoxicsubstance (e.g. an amino acid, etc.) to the first region 2225, 2250 toperform the procedure.

In aspects, the procedure may include an ablation, an excision, a cut, aburn, an RF ablation, an abrasion, radiosurgery, an ultrasonic ablation,a biopsy, delivery of a substance, etc. to the first region 2225, 2250.

In aspects, the follow up procedure may include delivery of energy to,delivery of a chemical to, providing thermal excitation to, delivery ofcurrent to, delivery of ultrasound energy to, cryogenically cooling,etc. the second region 2230, 2255.

In aspects, the first region 2225, 2250 and the second region 2230, 2255may be substantially collocated with each other, the second region 2230,2255 may be located closer to the organ 2203 than the first region 2225,2250, etc.

A system in accordance with the present disclosure may include asurgical tool for performing the procedure and/or follow on procedure tothe first region 2225, 2250 and/or the second region 2230, 2255respectively, a sensor coupled to the subject, the sensor configured tomonitor 2235, 2285 one or more of the physiologic parameters 2201, and afeedback mechanism for informing an operator of the outcome of theprocedure.

Some non-limiting examples of feedback generated by a feedback system inaccordance with the present disclosure include visual feedback, audiofeedback, indictors, a visual indicator, signal feedback, a tracing, anumerical readout, a pass/fail indicator, combinations thereof, and thelike.

A method for determining the durability of a procedure in accordancewith the present disclosure may include, applying a follow on procedureto a second region 2230, 2255 of a subject during follow up to apreviously performed procedure having been applied to the first region2225, 2250 and monitoring 2235, 2285 a physiologic parameter 2201 inaccordance with the present disclosure. If the physiologic parameter2201 does not change within a period of time after applying the followon procedure to the second region 2230, 2255, the procedure applied tothe first region 2225, 2250 is durable.

A method for predicting the extent to which a subject will respond to aprocedure in accordance with the present disclosure may include,applying a follow on procedure to a first region 2225, 2250 or to asecond region 2230, 2255 and monitoring 2235, 2285 a physiologicparameter 2201. If the physiologic parameter 2201 does not changesignificantly within a period of time after applying the follow onprocedure to the subject, then the subject may not be a good candidatefor a procedure in accordance with the present disclosure. If thephysiologic parameter 2201 changes significantly after applying thefollow on procedure to the subject, then the subject may be an idealcandidate for a procedure in accordance with the present disclosure. Inaspects, a significant change in the physiologic parameter may beindicated by a change of greater than 0.5%, greater than 1%, greaterthan 5%. In aspects, a significant increase in the physiologic parametermay be a favorable response to the follow on procedure.

Some non-limiting methods for performing a procedure in accordance withthe present disclosure are discussed herein.

In one non-limiting example, a method for addressing a surgical sitewithin a vessel (e.g. an artery, a vein, a renal artery, a micro-vessel,etc.) is considered. The method includes, monitoring one or more localphysiological signals (e.g. an evoked potential, a neurologicalactivity, MSNA, EMG, MMG, extracellular signal, sympathetic tonalchange, etc.) in accordance with the present disclosure at one or moremeasurement locations within the vessel to determine one or morereference signals; performing at least a portion of a surgical procedure(e.g. an ablation, an excision, a cut, a burn, an RF ablation, anabrasion, radiosurgery, an ultrasonic ablation, a biopsy, delivery of asubstance, etc.) in accordance with the present disclosure at or near toone or more surgical locations (e.g. proximal, distal, remotelytherefrom, and/or collocated with one or more of the measurementlocations); monitoring one or more local physiological signals at one ormore of the measurement locations to determine one or more updatedsignals; and comparing one or more reference signals with one or moreupdated signals to determine an extent of completion for the surgicalprocedure.

In aspects, the extent of completion may include a change, reductionand/or substantial elimination of at least a portion of one or more ofthe local physiological signals (e.g. reduction in amplitude of afrequency band, reduction in responsiveness, a change in a lag betweenmeasurement locations, a change in cross-talk between measurementlocations, substantial elimination of the signal, etc.)

In aspects, the extent of completion may include measuring a change incoherence between two or more signals obtained from sites affected bythe surgical procedure (i.e. from a first site distal to where thesurgical procedure was performed, and from a second site proximal towhere the surgical procedure was performed).

In aspects, the procedure may be to perform a temporary neurologicalblock. In this aspect, the method may be used to separate afferent andefferent traffic from either side of the temporary block, for furtheranalysis, diagnosis of disease, evaluation of neurological activity, orthe like. In aspects, a temporary block may be followed by a morepermanent block if the analysis demonstrates that such a substantiallypermanent block would be warranted.

The step of monitoring to determine an updated signal may be performedbefore, during, and/or after the step of performing at least a portionof the surgical procedure. In aspects, monitoring, stimulation, andablation may be performed in succession and/or in parallel.

In aspects, the method may include sweeping one or more electrodes overthe lumen wall while monitoring, stimulating, and/or ablating thesurface thereof. In aspects, simultaneous monitoring and sweeping may beused to generate a map of neurological activity along the lumen wall.

The step of performing at least a portion of the surgical procedure maybe repeated. Thus the method may be incrementally applied, so as to headtowards completion in a stepwise process without excessive applicationof the surgical procedure.

The method may include waiting after performing at least a portion ofthe surgical procedure. Monitoring may be performed during the waitingprocedure, perhaps so as to determine a recovery period for the localphysiological signal (i.e. a time period over which the localphysiological signal recovers). Such a recovery period may be anindication of the extent of completion.

In aspects, the method may include stimulating one or more stimulationlocations (proximal, distal, remotely therefrom, and/or collocated withone or more of the measurement locations and/or the surgical locations).The step of stimulating may be coordinated with the step of performingat least a portion of the surgical procedure, and/or with the step ofmonitoring to determine a reference and/or updated signal. Thestimulation may be provided in any form in accordance with the presentdisclosure. In one non-limiting example, the stimulation may include oneor more current pulses, one or more voltage pulses, combinationsthereof, or the like. The step of stimulation may be advantageous forassessing the updated signal at one or more measurement locations and/orbetween two or more measurement locations in the presence of backgroundnoise and/or local physiological activity.

In aspects, the method may include monitoring one or more remotephysiologic parameters in accordance with the present disclosure at aremote location (e.g. an alternative vessel, an organ, a ganglion, anerve, etc.) substantially removed from the immediate vicinity of thevessel to determine an updated remote physiological signal and/orreference remote physiological signal.

Some non-limiting examples of remote physiologic parameters that may bemonitored include water concentration, tone, blood oxygen saturation oflocal tissues, evoked potential, stimulation/sensing of nervousactivity, electromyography, temperature, blood pressure, vasodilation,vessel wall stiffness, muscle sympathetic nerve activity (MSNA), centralsympathetic drive (e.g. bursts per minute, bursts per heartbeat, etc.),tissue tone, blood flow (e.g. through an artery, through a renalartery), a blood flow differential signal (e.g. a significantly abnormaland or sudden change in blood flow within a structure of the body, avessel, an organ, etc.), blood perfusion (e.g. to an organ, an eye,etc.), a blood analyte level (e.g. a hormone concentration,norepinephrine, catecholamine, renin, angiotensin II, an ionconcentration, a water level, an oxygen level, etc.), nerve traffic(e.g. post ganglionic nerve traffic in the peroneal nerve, celiacganglion, superior mesenteric ganglion, aorticorenal ganglion, renalganglion, and/or related nervous system structures), combinationsthereof, and the like.

The updated remote physiological signal and/or reference remotephysiological signal may be combined and/or compared with one or morereference signals, and/or one or more updated signals in order todetermine the extent of completion, as part of a decision makingprocess, and/or as part of a surgical control system (i.e. so as todetermine whether to continue with, stop, or alter the surgicalprocedure).

The method may include selecting a surgical location. The step ofselection may depend upon one or more monitoring steps, proximity to analternative surgical location (i.e. perhaps a previously treatedsurgical location, etc.).

In aspects, the method may include sweeping the lumen while monitoringin order to localize one or more anatomical sites of interest, one ormore regions of abnormal activity, etc.

In aspects, the steps of monitoring may be completed sequentially.Alternatively, additionally, or in combination, the steps of monitoringmay be effectively continuously applied through the procedure. Thecomparison may be made using one or more data points obtained from oneor more steps of monitoring. The comparison may be made via algorithmiccombination of one or more measurements.

In aspects, the step of monitoring may be used to extract one or moreelectrophysiologic parameters during a first period and monitoring anapplied field (i.e. as caused by a stimulation and/or ablation event)during a second period.

In aspects, the method may include generating a topographical map fromthe one or more measurements (e.g. from one or more of the signals). Themethod may include determining a topographical map of physiologicalfunctionality in the vicinity of the surgical site derived from one ormore of the physiological signals. The method may include updating thetopographical map after the step of performing at least a portion of thesurgical procedure. The method may include generating the map during asweeping process (i.e. a longitudinal sweep, a circumferential sweep, ahelical sweep, etc.).

In aspects, the method may include placement of a plurality of surgicaltools, one or more surgical tools (i.e. a procedural tool) placed so asto access one or more of the surgical locations, and one or moresurgical tools (i.e. a monitoring tool) placed so as to access one ormore of the monitoring locations. In one non-limiting example, aprocedural tool may be placed in a first vessel (e.g. a renal artery, aleft renal artery, etc.) and a monitoring tool may be placed into asecond vessel (e.g. an opposing renal artery, a right renal artery, afemoral artery, an iliac artery, etc.). Thus, the monitoring tool may beused to monitor one or more of the measurement locations in the secondvessel. The procedural tool may be used to surgically treat one or moresurgical locations in the first vessel. Additionally, alternatively, orin combination, the procedural tool may monitor one or more monitoringlocations in the first vessel, perhaps in combination with monitoringperformed in the second vessel by the monitoring tool.

In aspects, the method may be performed with one or more surgical toolsin accordance with the present disclosure.

One or more steps of monitoring may be performed with one or moresensing tips in accordance with the present disclosure.

One or more steps of performing at least a portion of the surgicalprocedure may be performed with one or more sensing tips in accordancewith the present disclosure.

In one non-limiting example of a method for RF ablating tissue, thelocal tissue tone may be measured before, during, between individual RFpulses, and/or after a train of RF pulses. As the local tissue tonechanges during application of the RF pulses, the tonal changes may beused to determine the extent of the therapy. As the RF ablation processis applied to the adjacent tissues (perhaps via one or more sensingtips), the tonal measurements (as determined by one or more sensingtips, perhaps the same tip through which the RF signal may be applied)may be monitored to determine an extent of completion of the procedure.Such an approach may be advantageous as the tonal measurement techniquesmay not be significantly affected by the local RF currents associatedwith the RF ablation procedure.

In aspects, an interventionalist/proceduralist may insert a catheter inaccordance with the present disclosure into the aorta from either thesuperior or inferior approach (brachial or femoral arteries) andselectively cannulate the renal artery. In aspects, a guiding cathetermay be used for this purpose. In aspects, a microsurgical tool inaccordance with the present disclosure may be placed through the guidingcatheter. In aspects, one or more regions of the microsurgical tool maybe deployed thus allowing one or more electrodes included therein tobias against the lumen of the renal artery. Such a configuration may beadvantageous to establish excellent mechanical and electrical contactwith the walls of the renal artery.

In aspects, the electrodes may be made to puncture the vessel wall fromthe lumen side. The electrodes may be expandable and/or retractable,exiting in a stable pattern of 1 to 6, or more microfingers that permitstability and counter-opposition force to cause penetration of one ormore of the electrodes into the intima, media, or adventitia of thelumen (i.e. artery, vein, etc.) to be measured. In aspects, one or moreelectrodes may be configured for microscopic or macroscopic spatialrecording. Following a suitable period of recording, the device may bewithdrawn into the guiding catheter and removed from the body.

It will be appreciated that additional advantages and modifications willreadily occur to those skilled in the art. Therefore, the disclosurespresented herein and broader aspects thereof are not limited to thespecific details and representative embodiments shown and describedherein. Accordingly, many modifications, equivalents, and improvementsmay be included without departing from the spirit or scope of thegeneral inventive concept as defined by the appended claims and theirequivalents.

What is claimed is:
 1. A system, comprising: a tool comprising: adelivery catheter; one or more microfingers having substantiallyelongate structures; a plurality of sensing tips electrically andmechanically coupled to the one or more microfingers, the plurality ofsensing tips configured to interface with a wall of a lumen coupled toan organ of a subject on deployment of the one or more microfingers fromthe delivery catheter; and a local control circuit embedded in thesubstantially elongate structure of at least one of the one or moremicrofingers; and a feedback system coupled to the tool; wherein thetool is configured: to apply a procedure to a first region in a vicinityof the lumen via delivery of at least one of energy and a chemical to atleast one of the plurality of sensing tips under control of the localcontrol circuit; and to apply a follow on procedure to a second regionin the vicinity of the lumen via delivery of at least one of energy anda chemical to at least one of the plurality of sensing tips undercontrol of the local control circuit, the second region being locatedequidistant or closer to the organ than the first region; to monitor oneor more physiologic parameters of the subject utilizing at least one ofthe plurality of sensing tips after application of the follow onprocedure; to condition one or more signals representing the monitoredphysiologic parameters utilizing the local control circuit; and toconvey the conditioned one or more signals representing the monitoredphysiologic parameters to the feedback system; wherein the feedbacksystem is configured: to receive the conditioned one or more signalsrepresenting the monitored physiologic parameters; to analyze thereceived signals to determine one or more changes in the physiologicparameters; and to convey an outcome of the procedure to an operatorbased upon the determined changes in the physiologic parameters.
 2. Thesystem in accordance with claim 1, wherein the feedback system isconfigured to indicate to the operator a successful outcome for theprocedure if one or more of the physiologic parameters do notsubstantially change during a predetermined period following applicationof the follow on procedure.
 3. The system in accordance with claim 1,wherein the feedback system is configured to indicate to the operator anunsuccessful outcome for the procedure if one or more of the physiologicparameters substantially change during a predetermined period followingapplication of the follow on procedure.
 4. The system in accordance withclaim 1, wherein at least one of the first region and the second regionsubstantially surround the circumference of the lumen.
 5. The system inaccordance with claim 1, wherein the procedure is selected from thegroup consisting of an ablation, an excision, a cut, a burn, a radiofrequency ablation, freezing, a microwave ablation, radiosurgery, anultrasonic ablation, an abrasion, a biopsy, and delivery of a substance.6. The system in accordance with claim 1, wherein the follow onprocedure is selected from the group consisting of an ablation, anexcision, a cut, a burn, a radio frequency ablation, freezing, amicrowave ablation, radiosurgery, an ultrasonic ablation, an abrasion, abiopsy, stimulation, and delivery of a substance.
 7. The system inaccordance with claim 1, wherein the one or more physiologic parametersare selected from water concentration, tone, blood oxygen saturation oflocal tissues, evoked potential, electrolyte or solute concentration,stimulation of nervous activity, sensing of nervous activity,electromyography, temperature, blood pressure, vasodilation, vessel wallstiffness, muscle sympathetic nerve activity (MSNA), central sympatheticdrive, a mechanomyographic signal, a local field potential, anelectroacoustic event, central sympathetic drive, tissue tone, nervetraffic, and combinations thereof.
 8. The system in accordance withclaim 2, wherein the predetermined period is longer than 5 seconds (s),longer than 30 s, longer than 1 minute (min), longer than 3 min, longerthan 5 min, or longer than 8 min.
 9. The system in accordance with claim1, wherein a timespan between application of the procedure andapplication of the follow on procedure is longer than 5 s, longer than30 s, longer than 1 min, longer than 3 min, longer than 5 min, or longerthan 8 min.
 10. The system in accordance with claim 1, wherein the toolis further configured to apply one or more subsequent follow onprocedures to one of the first region and the second region of thesubject under control of the local control circuit based on feedbackreceived from the feedback system.
 11. The system in accordance withclaim 10, wherein the feedback system is configured to indicate to theoperator a durable outcome for the procedure if one or more of thephysiologic parameters do not substantially change during apredetermined period following application of the one or more subsequentfollow on procedures.
 12. The system in accordance with claim 1, whereinone or more of the plurality of sensing tips are sized and dimensionedto be deliverable to and to interface with at least one of the firstregion and the second region.
 13. The system in accordance with claim 1,wherein the plurality of sensing tips comprise a balloon cathetercomprising a balloon with a surface, the balloon shaped and dimensionedfor placement within the lumen, the balloon comprising one or moreenergy elements and chemical delivery elements arranged along thesurface thereof, the one or more energy elements and chemical deliveryelements configured to perform at least one of the procedure and thefollow on procedure.
 14. The system in accordance with claim 1, furthercomprising one or more sensors, separate from the tool, configured tomonitor one or more physiologic parameters of the subject.
 15. Thesystem in accordance with claim 14, wherein at least one of the sensorsis a pressure sensor sized to fit within a lumen in the body, configuredto measure a blood pressure response therefrom.
 16. The system inaccordance with claim 1, wherein the system performs at least one of adenervation and a neuromodulation procedure in the vicinity of a renalartery.
 17. The system in accordance with claim 1, wherein the systemassesses the durability of at least one of a denervation and aneuromodulation procedure.
 18. The system in accordance with claim 1,wherein the one or more microfingers comprise a longitudinal wire cageconfigured to maintain contact with the wall of the lumen withoutinhibiting flow of fluids through the lumen.
 19. The system of claim 18,wherein the tool further comprises a guidewire configured to assist withguiding the longitudinal wire cage to the first region and the secondregion.
 20. The system of claim 19, wherein the tool further comprises adistal ringlet configured to accommodate passage of the guidewirethrough the longitudinal wire cage.
 21. The system of claim 18, whereinthe longitudinal wire cage is configured such that a first microfingerarray comprising a first subset of the plurality of sensing tips biasesagainst the wall of the lumen in the first region while a secondmicrofinger array comprising a second subset of the plurality of sensingtips biases against the wall of the lumen in the second region during asingle placement of the tool.
 22. The system of claim 1, wherein the oneor more microfingers comprise a first microfinger array and at least asecond microfinger array, the first microfinger array and the secondmicrofinger array comprising respective radially biased flexuralsprings.
 23. The system of claim 22, wherein the tool comprises a firstguiding arm coupled to the first microfinger array and a second guidingarm coupled to the second microfinger array.
 24. The system of claim 23,wherein the second guiding arm is configured to deploy from within thefirst guiding arm.
 25. The system of claim 22, wherein the one or moremicrofingers are configured such that a first subset of the plurality ofsensing tips coupled to the radially biased flexural springs of thefirst microfinger array bias against the wall of the lumen in the firstregion while a second subset of the plurality of sensing tips coupled tothe radially biased flexural springs of the second microfinger arraybias against the wall of the lumen in the second region during a singleplacement of the tool.
 26. The system of claim 1, wherein the localcontrol circuit is configured to route signal traffic to and fromrespective ones of the plurality of sensing tips.
 27. The system ofclaim 1, wherein the local control circuit is configured to applyradiofrequency current locally between two or more of the plurality ofsensing tips.
 28. The system of claim 1, wherein the system furthercomprises one or more sensors external to the tool, and wherein thelocal control circuit is configured to apply radiofrequency currentbetween one or more of the plurality of sensing tips and the one or moresensors external to the tool.
 29. The system of claim 1, wherein the oneor more microfingers are configured to bend within the body of thesubject on deployment from the delivery catheter to bias towards thewall of the lumen.
 30. The system of claim 1, wherein the tool isconfigured to condition the one or more signals representing themonitored physiologic parameters by utilizing the local control circuitto convert one or more signals representing the monitored physiologicparameters to digital form prior to conveying the conditioned one ormore signals to the feedback system.
 31. The system of claim 1, whereinthe tool is configured to condition the one or more signals representingthe monitored physiologic parameters by utilizing the local controlcircuit as a low impedance source.
 32. The system of claim 1, whereinthe plurality of sensing tips comprise a networked array of sensing tipsmultiplexed together using the local control circuit.
 33. The system ofclaim 1, wherein the feedback system comprises an extracorporeal system.34. The system of claim 33, wherein the local control circuit isconfigured to digitally convey the conditioned one or more signals tothe extracorporeal feedback system.
 35. The system of claim 34, whereinthe local control circuit is configured to selectively exchange datawith the extracorporeal feedback system relating to individual ones ofthe plurality of sensing tips.
 36. The system of claim 34, wherein thelocal control circuit is configured exchange switch data, control dataand radiofrequency pulse routing data with the extracorporeal feedbacksystem.